Johannes Veldhuis

Summary

Affiliation: Mayo Clinic
Country: USA

Publications

  1. ncbi Changes in pituitary function with ageing and implications for patient care
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, MN 55905, USA
    Nat Rev Endocrinol 9:205-15. 2013
  2. ncbi Sex steroids, GHRH, somatostatin, IGF-I, and IGFBP-1 modulate ghrelin's dose-dependent drive of pulsatile GH secretion in healthy older men
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, National Institutes of Health Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 97:4753-60. 2012
  3. ncbi Analysis of the impact of intravenous LH pulses versus continuous LH infusion on testosterone secretion during GnRH-receptor blockade
    Johannes D Veldhuis
    Endocrine Research Unit, Dept of Internal Medicine, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Regul Integr Comp Physiol 303:R994-R1002. 2012
  4. ncbi Model-based evaluation of growth hormone secretion
    Johannes D Veldhuis
    Department of Medicine, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, Minnesota, USA
    Methods Enzymol 514:231-48. 2012
  5. ncbi Dynamic testosterone responses to near-physiological LH pulses are determined by the time pattern of prior intravenous LH infusion
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, MN, USA
    Am J Physiol Endocrinol Metab 303:E720-8. 2012
  6. ncbi Logistic model of glucose-regulated C-peptide secretion: hysteresis pathway disruption in impaired fasting glycemia
    Daniel M Keenan
    Department of Statistics, University of Virginia, Charlottesville, VA, USA
    Am J Physiol Endocrinol Metab 303:E397-409. 2012
  7. ncbi Distinct metabolic surrogates predict basal and rebound GH secretion after glucose ingestion in men
    Ali Iranmanesh
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 97:2172-9. 2012
  8. ncbi Glucose ingestion acutely lowers pulsatile LH and basal testosterone secretion in men
    Ali Iranmanesh
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Endocrinol Metab 302:E724-30. 2012
  9. ncbi Gender, sex-steroid, and secretagogue-selective recovery from growth hormone-induced feedback in older women and men
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 96:2540-7. 2011
  10. ncbi Estimation of the size and shape of GH secretory bursts in healthy women using a physiological estradiol clamp and variable-waveform deconvolution model
    Johannes D Veldhuis
    Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
    Am J Physiol Regul Integr Comp Physiol 293:R1013-21. 2007

Research Grants

  1. Age-Dependent Estrogen-Independent Mechanism of Hyposomatotropism in Women
    Johannes D Veldhuis; Fiscal Year: 2010
  2. Analytical Reconstruction of Feedback Signaling in Aging Men
    Johannes Veldhuis; Fiscal Year: 2007
  3. ACTIONS OF TESTOSTERONE ON THE AGING MALE GH AXIS
    Johannes Veldhuis; Fiscal Year: 2007
  4. ACTIONS OF ESTROGEN IN MATURING GRAAFIAN FOLLICLES
    Johannes Veldhuis; Fiscal Year: 2005
  5. THE AGING GH AXIS IN POSTMENOPAUSAL WOMEN
    Johannes Veldhuis; Fiscal Year: 2005
  6. ENSEMBLE MODEL OF STRESS ACTH-ADRENAL AXIS
    Johannes Veldhuis; Fiscal Year: 2005
  7. Novel Active Repressor Model of Human LDL-Receptor Regulation
    Johannes Veldhuis; Fiscal Year: 2007
  8. Mechanistic bases for age-related androgen deficiency
    Johannes Veldhuis; Fiscal Year: 2007
  9. Aging Systems in Geriatrics: the Male Gonadal Axis
    Johannes D Veldhuis; Fiscal Year: 2010
  10. Ensemble Control of ACTH Secretion: Impact of Gender
    Johannes D Veldhuis; Fiscal Year: 2010

Collaborators

Detail Information

Publications112 found, 100 shown here

  1. ncbi Changes in pituitary function with ageing and implications for patient care
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, MN 55905, USA
    Nat Rev Endocrinol 9:205-15. 2013
    ..The aim of this article is to critically discuss the mechanisms mediating clinical facets of changes in the hypothalamic-pituitary axis during ageing, and the extent to which confounding factors operate to obscure ageing-related effects...
  2. ncbi Sex steroids, GHRH, somatostatin, IGF-I, and IGFBP-1 modulate ghrelin's dose-dependent drive of pulsatile GH secretion in healthy older men
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, National Institutes of Health Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 97:4753-60. 2012
    ..Ghrelin is a potent endogenous stimulator of GH secretion. However, clinical factors that regulate ghrelin dose-responsiveness are incompletely defined...
  3. ncbi Analysis of the impact of intravenous LH pulses versus continuous LH infusion on testosterone secretion during GnRH-receptor blockade
    Johannes D Veldhuis
    Endocrine Research Unit, Dept of Internal Medicine, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Regul Integr Comp Physiol 303:R994-R1002. 2012
    ..These data introduce the question whether blood T patterns in turn supervise distinctive target-tissue responses...
  4. ncbi Model-based evaluation of growth hormone secretion
    Johannes D Veldhuis
    Department of Medicine, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, Minnesota, USA
    Methods Enzymol 514:231-48. 2012
    ....
  5. ncbi Dynamic testosterone responses to near-physiological LH pulses are determined by the time pattern of prior intravenous LH infusion
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, MN, USA
    Am J Physiol Endocrinol Metab 303:E720-8. 2012
    ..Collectively, these data indicate that in vivo dynamics of LH-stimulated T secretion under standardized conditions in men depend on the prior time mode of LH delivery in the bloodstream...
  6. ncbi Logistic model of glucose-regulated C-peptide secretion: hysteresis pathway disruption in impaired fasting glycemia
    Daniel M Keenan
    Department of Statistics, University of Virginia, Charlottesville, VA, USA
    Am J Physiol Endocrinol Metab 303:E397-409. 2012
    ..Pathway-defined analytic models of this kind may aid in the search for prediabetes biomarkers...
  7. ncbi Distinct metabolic surrogates predict basal and rebound GH secretion after glucose ingestion in men
    Ali Iranmanesh
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 97:2172-9. 2012
    ..GH secretion declines rapidly after glucose ingestion and then recovers to higher-than-baseline levels (rebound GH release)...
  8. ncbi Glucose ingestion acutely lowers pulsatile LH and basal testosterone secretion in men
    Ali Iranmanesh
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Endocrinol Metab 302:E724-30. 2012
    ..30). In conclusion, glucose ingestion suppresses pulsatile LH and basal T secretion acutely in healthy men. Suppression is influenced by age, glucose, adiponectin, and insulin concentrations...
  9. ncbi Gender, sex-steroid, and secretagogue-selective recovery from growth hormone-induced feedback in older women and men
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 96:2540-7. 2011
    ..GH negatively regulates its own secretion. How gender, sex steroids, and secretagogues modulate GH autofeedback is not known...
  10. ncbi Estimation of the size and shape of GH secretory bursts in healthy women using a physiological estradiol clamp and variable-waveform deconvolution model
    Johannes D Veldhuis
    Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
    Am J Physiol Regul Integr Comp Physiol 293:R1013-21. 2007
    ..001). Accordingly, age selectively determines both the size (amount) and shape (waveform) of GH secretory bursts in healthy women independently of the short-term estrogen milieu...
  11. ncbi Peripheral estrogen receptor-alpha selectively modulates the waveform of GH secretory bursts in healthy women
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo Medical and Graduate Schools, Clinical Translational Research Unit, Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Regul Integr Comp Physiol 293:R1514-21. 2007
    ..The collective data indicate that peripheral ERalpha-dependent mechanisms determine the shape (waveform) of in vivo GH secretory bursts and that such mechanisms operate with secretagogue selectivity...
  12. ncbi Aging and hormones of the hypothalamo-pituitary axis: gonadotropic axis in men and somatotropic axes in men and women
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Mayo Clinical Translational Research Center, School of Graduate Medical Education, Mayo Clinic, Rochester, MN 55905, USA
    Ageing Res Rev 7:189-208. 2008
    ....
  13. ncbi Twenty-four hour continuous ghrelin infusion augments physiologically pulsatile, nycthemeral, and entropic (feedback-regulated) modes of growth hormone secretion
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Clinical Translational Science Unit, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 93:3597-603. 2008
    ..Ghrelin is a 28-amino acid acylated peptide that potentiates GHRH stimulation and opposes somatostatin inhibition acutely. Whether prolonged ghrelin administration can sustain physiological patterns of GH secretion remains unknown...
  14. ncbi Secretagogues govern GH secretory-burst waveform and mass in healthy eugonadal and short-term hypogonadal men
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo Medical and Graduate Schools, Mayo Clinic, Rochester, Minnesota 55905, USA
    Eur J Endocrinol 159:547-54. 2008
    ..GH pulses are putatively initiated by hypothalamic GH-releasing hormone (GHRH), amplified by GH-releasing peptide (GHRP), and inhibited by somatostatin (SS)...
  15. ncbi Estradiol supplementation in postmenopausal women attenuates suppression of pulsatile growth hormone secretion by recombinant human insulin-like growth factor type I
    Johannes D Veldhuis
    Department of Medicine, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 93:4471-8. 2008
    ..One possibility is that estrogen not only enhances stimulation by secretagogues but also attenuates negative feedback by systemic IGF-I. SITE: The study took place at an academic medical center...
  16. ncbi The aging male hypothalamic-pituitary-gonadal axis: pulsatility and feedback
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Mayo Clinic College of Medicine, Mayo Clinic, 200 First Steet SW, Rochester, MN 55905, United States
    Mol Cell Endocrinol 299:14-22. 2009
    ..The present review highlights integrative adaptations in the aging male hypothalamic-pituitary-gonadal axis, as assessed by recent objective ensemble models of the axis as a whole...
  17. ncbi Tripartite control of growth hormone secretion in women during controlled estradiol repletion
    Johannes D Veldhuis
    Endocrine Research Unit 9, General Clinical Research Center, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, Rochester, MN 55905, USA
    J Clin Endocrinol Metab 92:2336-45. 2007
    ....
  18. ncbi Estradiol potentiates ghrelin-stimulated pulsatile growth hormone secretion in postmenopausal women
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 91:3559-65. 2006
    ..Ghrelin and an estrogen-rich milieu individually amplify pulsatile GH secretion by increasing the amount of hormone released per burst. However, how these distinct agonists interact in controlling pulsatile GH output is not known...
  19. ncbi Distinctive inhibitory mechanisms of age and relative visceral adiposity on growth hormone secretion in pre- and postmenopausal women studied under a hypogonadal clamp
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 90:6006-13. 2005
    ..Aging, body composition, and sex steroids jointly determine GH production. However, the actions of any given factor are confounded by the effects of the other two...
  20. ncbi Testosterone supplementation in healthy older men drives GH and IGF-I secretion without potentiating peptidyl secretagogue efficacy
    Johannes D Veldhuis
    Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, MN 55905, USA
    Eur J Endocrinol 153:577-86. 2005
    ..e. reduces opposition by hypothalamic somatostatin) and (iii) abdominal visceral fat (AVF) mass is a negative determinant of specific secretagogue-stimulated GH secretion...
  21. ncbi Administration of recombinant human GHRH-1,44-amide for 3 months reduces abdominal visceral fat mass and increases physical performance measures in postmenopausal women
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, General Clinical Research Center, Mayo School of Graduate Medical Education, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
    Eur J Endocrinol 153:669-77. 2005
    ....
  22. ncbi Sex-steroid control of the aging somatotropic axis
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
    Endocrinol Metab Clin North Am 34:877-93, viii. 2005
  23. ncbi Aging-related adaptations in the corticotropic axis: modulation by gender
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Mayo School of Graduate Medical Education, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
    Endocrinol Metab Clin North Am 34:993-1014, x-xi. 2005
  24. ncbi Somatotropic and gonadotropic axes linkages in infancy, childhood, and the puberty-adult transition
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Mayo Medical School, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    Endocr Rev 27:101-40. 2006
    ..Significant advances in systems biology will be needed to address these challenges...
  25. ncbi Ghrelin potentiates growth hormone secretion driven by putative somatostatin withdrawal and resists inhibition by human corticotropin-releasing hormone
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 91:2441-6. 2006
    ..Beyond the capability of ghrelin to synergize with GHRH, little is known about multipeptide modulation of ghrelin's actions in humans...
  26. ncbi Sex-steroid modulation of growth hormone (GH) secretory control: three-peptide ensemble regulation under dual feedback restraint by GH and IGF-I
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, General Clinical Research Center, Mayo Medical and Graduate School of Medicine, Mayo Clinic, Rochester, MN 55905, USA
    Endocrine 22:25-40. 2003
    ..In conclusion, the present conceptual platform of tri-peptide-directed feedforward and GH/IGF-I-mediated feedback should aid in unraveling some of the complex regulatory dynamics targeted by sex-steroid hormones...
  27. ncbi Motivations and methods for analyzing pulsatile hormone secretion
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Mayo Medical School, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA
    Endocr Rev 29:823-64. 2008
    ..This review will focus on the motivations driving and the methodologies used for such analyses...
  28. ncbi Testosterone supplementation in older men restrains insulin-like growth factor's dose-dependent feedback inhibition of pulsatile growth hormone secretion
    Johannes D Veldhuis
    Department of Medicine, Endocrine Research Unit, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 94:246-54. 2009
    ..The causal mechanisms are unknown. Candidates include deficient feedforward (stimulation) by endogenous secretagogues and excessive feedback (inhibition) by GH or IGF-I due to age and/or relative hypoandrogenemia...
  29. ncbi Aromatase and 5alpha-reductase inhibition during an exogenous testosterone clamp unveils selective sex steroid modulation of somatostatin and growth hormone secretagogue actions in healthy older men
    Johannes D Veldhuis
    Department of Internal Medicine and Pediatrics, Endocrine Research Unit, Clinical Translational Research Center, Mayo Medical and Graduate Schools, Mayo Clinic, Rochester Minnesota 55901, USA
    J Clin Endocrinol Metab 94:973-81. 2009
    ..How endogenous testosterone (Te), 5alpha-dihydrotestosterone (DHT), and estradiol (E(2)) regulate pulsatile GH secretion is not understood...
  30. ncbi Older men exhibit reduced efficacy of and heightened potency downregulation by intravenous pulses of recombinant human LH: a study in 92 healthy men
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA
    Am J Physiol Endocrinol Metab 302:E117-22. 2012
    ..27). Assuming stable bioactivity of infused recombinant human LH, these novel data indicate that factors associated with age and BMI attenuate LH efficacy and testis sensitivity and augment Leydig cell downregulation in healthy men...
  31. ncbi Regulated recovery of pulsatile growth hormone secretion from negative feedback: a preclinical investigation
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Regul Integr Comp Physiol 301:R1143-52. 2011
    ..The ensemble factors identified in this preclinical investigation enlarge the dynamic model of GH control in humans...
  32. ncbi Tripartite control of dynamic ACTH-cortisol dose responsiveness by age, body mass index, and gender in 111 healthy adults
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 96:2874-81. 2011
    ..initial and delayed) dynamic dose-responsive effects on target glands, wherein down-regulating dynamics are inferable on a time scale of single pulses...
  33. ncbi Complex regulation of GH autofeedback under dual-peptide drive: studies under a pharmacological GH and sex steroid clamp
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Center for Translational Science Activities, MayoClinic, Rochester, MN 55905, USA
    Am J Physiol Endocrinol Metab 300:E1158-65. 2011
    ..To the degree that the pharmacological sex steroid, GH, and dual-peptide clamps provide prephysiological regulatory insights, these outcomes suggest major determinants of pulsatile GH secretion in the feedback domain...
  34. ncbi Gender, age, body mass index, and IGF-I individually and jointly determine distinct GH dynamics: analyses in one hundred healthy adults
    Johannes D Veldhuis
    Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 96:115-21. 2011
    ..GH secretion is quantifiable as mean, peak, and nadir GH concentrations; degree of irregularity (approximate entropy); and spikiness (brief staccato-like fluctuations)...
  35. ncbi Age disrupts androgen receptor-modulated negative feedback in the gonadal axis in healthy men
    Johannes D Veldhuis
    Mayo School of Graduate Medical Education, Mayo Clinic, 200 First St SW Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Endocrinol Metab 299:E675-82. 2010
    ..001). These data suggest the hypothesis that topographically selective androgen receptor pathways mediate brain-predominant and pituitary-dependent feedback mechanisms in healthy men...
  36. ncbi Regulation of complex pulsatile and rhythmic neuroendocrine systems: the male gonadal axis as a prototype
    Johannes D Veldhuis
    Department of Medicine, Endocrine Research Unit, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, Minnesota, United States of America
    Prog Brain Res 181:79-110. 2010
    ..In this manner, each neuroendocrine system is viewed as a whole, rather than the sum of individual parts...
  37. ncbi A pegylated growth hormone receptor antagonist, pegvisomant, does not enter the brain in humans
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Neurology, Mayo School of Graduate Medical Education, Clinical Translation Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 95:3844-7. 2010
    ..GH receptors exist in the hippocampus, cerebral cortex, and hypothalamus, possibly influencing mood, cortical blood flow, and neuronal growth and mediating negative feedback...
  38. ncbi Kinetics of removal of intravenous testosterone pulses in normal men
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    Eur J Endocrinol 162:787-94. 2010
    ....
  39. ncbi Basal, pulsatile, entropic (patterned), and spiky (staccato-like) properties of ACTH secretion: impact of age, gender, and body mass index
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo Medical School, Mayo School of Graduate Medical Education, Center for Translational Science Activities, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 94:4045-52. 2009
    ..pulsatile, basal, pattern-defined regularity [approximate entropy (ApEn)] and spikiness (sharp, brief excursions). Whether the same determinants apply to ACTH secretion is not known...
  40. ncbi Regulation of basal, pulsatile, and entropic (patterned) modes of GH secretion in a putatively low-somatostatin milieu in women
    Johannes D Veldhuis
    Departments of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
    Am J Physiol Endocrinol Metab 297:E483-9. 2009
    ..Therefore, both factors must be considered in framing hypotheses of endogenous GH drive...
  41. ncbi Relative effects of estrogen, age, and visceral fat on pulsatile growth hormone secretion in healthy women
    Johannes D Veldhuis
    Departments of Internal Medicine, Endocrine Research Unit, Clinical Translational Research Unit, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, Rochester, Minnesota, USA
    Am J Physiol Endocrinol Metab 297:E367-74. 2009
    ..These data establish that age, estrogen status, and AVF are triple covariates of continuous peptide-secretagogue drive of pulsatile GH secretion in women. Each factor must be controlled for to allow valid comparisons of GH-axis activity...
  42. ncbi Preservation of GHRH and GH-releasing peptide-2 efficacy in young men with experimentally induced hypogonadism
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    Eur J Endocrinol 161:293-300. 2009
    ..Somatostatin (SS), GHRH, GH-releasing peptide (GHRP), and the sex-steroid milieu regulate GH secretion...
  43. ncbi Factors other than sex steroids modulate GHRH and GHRP-2 efficacies in men: evaluation using a GnRH agonist/testosterone clamp
    Johannes D Veldhuis
    Department of Medicine, Endocrine Research Unit, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 94:2544-50. 2009
    ..Sex steroids are prominent regulators of pulsatile GH secretion. Hypothesis: An experimentally controlled sex-steroid milieu will permit detection of nonsteroidal factors that determine GH secretion...
  44. ncbi Novel relationships of age, visceral adiposity, insulin-like growth factor (IGF)-I and IGF binding protein concentrations to growth hormone (GH) releasing-hormone and GH releasing-peptide efficacies in men during experimental hypogonadal clamp
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 94:2137-43. 2009
    ..Sex steroids influence GH secretion in complex ways...
  45. ncbi Determinants of GH-releasing hormone and GH-releasing peptide synergy in men
    Johannes D Veldhuis
    Mayo School of Graduate Medical Education, Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Endocrinol Metab 296:E1085-92. 2009
    ..002). In conclusion, a paradigm examining GHRH-GHRP synergy under a sex steroid clamp reveals highly selective control of basal, pulsatile, and synergistic peptide-driven GH secretion by AVF, E(2), and IGF-I in healthy men...
  46. ncbi Noninvasive analytical estimation of endogenous GnRH drive: analysis using graded competitive GnRH-receptor antagonism and a calibrating pulse of exogenous GnRH
    Daniel M Keenan
    Department of Statistics, University of Virginia, Charlottesville, Virginia 22904, USA
    Endocrinology 152:4882-93. 2011
    ..We conclude that combining experimental and analytical strategies may provide a noninvasive means to investigate and decipher feedback determinants of unobserved endocrine signal(s)...
  47. ncbi Contrasting negative-feedback control of endogenously driven and exercise-stimulated pulsatile growth hormone secretion in women and men
    Johannes D Veldhuis
    Department of Internal Medicine, Division of Endocrinology and Metabolism, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 89:840-6. 2004
    ....
  48. ncbi Contributions of gender and systemic estradiol and testosterone concentrations to maximal secretagogue drive of burst-like growth hormone secretion in healthy middle-aged and older adults
    Johannes D Veldhuis
    Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 89:6291-6. 2004
    ..86, P < 0.001) strongly predict responses to GHRP-2 only. We conclude that among healthy middle-aged and older adults, the action of GHRP is uniquely determined by gender and physiological concentrations of testosterone and estradiol...
  49. ncbi Erosion of endogenous testosterone-driven negative feedback on pulsatile luteinizing hormone secretion in healthy aging men
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, 200 First Street Southwest, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 89:5753-61. 2004
    ....
  50. ncbi Age diminishes the testicular steroidogenic response to repeated intravenous pulses of recombinant human LH during acute GnRH-receptor blockade in healthy men
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Endocrinol Metab 288:E775-81. 2005
    ..Whether more prolonged pulsatile LH stimulation would normalize this inferred defect is unknown...
  51. ncbi A tripeptidyl ensemble perspective of interactive control of growth hormone secretion
    Johannes D Veldhuis
    Mayo Medical and Graduate School of Medicine, Mayo Clinic, Rochester, MN 55905, USA
    Horm Res 60:86-101. 2003
    ..This concept is highlighted from the viewpoint of sex steroid- and age-dependent modulation of the peptide trilogy listed above...
  52. ncbi Experimentally induced androgen depletion accentuates ethnicity-related contrasts in luteinizing hormone secretion in asian and caucasian men
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 90:1632-8. 2005
    ..Therefore, we postulate that physiological nonuniformity of sex steroid-dependent negative feedback in particular may contribute to populational diversity in LH regulation...
  53. ncbi Age and testosterone feedback jointly control the dose-dependent actions of gonadotropin-releasing hormone in healthy men
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 90:302-9. 2005
    ..We conclude that a 3-fold interaction among GnRH dose, testosterone concentration, and age governs GnRH action, and age determines both testosterone-modulated and testosterone-independent actions of GnRH...
  54. ncbi Short-term aromatase-enzyme blockade unmasks impaired feedback adaptations in luteinizing hormone and testosterone secretion in older men
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 90:211-8. 2005
    ..Thus, aging alters expected hypothalamopituitary-gonadal adaptations to short-term partial estrogen depletion in healthy men...
  55. ncbi Physiological control of pituitary hormone secretory-burst mass, frequency, and waveform: a statistical formulation and analysis
    Daniel M Keenan
    Division of Endocrinology and Metabolism, Dept of Internal Medicine, Mayo Medical School and Graduate School of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Regul Integr Comp Physiol 285:R664-73. 2003
    ..Further studies will be required to assess the generality of the foregoing distinctive control mechanisms in other hypothalamo-pituitary axes...
  56. ncbi Estradiol supplementation enhances submaximal feed-forward drive of growth hormone (GH) secretion by recombinant human GH-releasing hormone-1,44-amide in a putatively somatostatin-withdrawn milieu
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 88:5484-9. 2003
    ....
  57. ncbi Pulsatile intravenous infusion of recombinant human luteinizing hormone under acute gonadotropin-releasing hormone receptor blockade reconstitutes testosterone secretion in young men
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate School of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 89:4474-9. 2004
    ..Whether a comparable near-physiological paradigm can maintain human Leydig-cell testosterone production for a more extended interval is not known...
  58. ncbi Estradiol supplementation modulates growth hormone (GH) secretory-burst waveform and recombinant human insulin-like growth factor-I-enforced suppression of endogenously driven GH release in postmenopausal women
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 89:1312-8. 2004
    ..Based upon companion modeling data, we postulate that E(2) facilitates the upstroke and IGF-I enforces the downstroke of high-amplitude GH secretory bursts in estrogen-replete individuals...
  59. ncbi Short-term testosterone supplementation relieves growth hormone autonegative feedback in men
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 89:1285-90. 2004
    ..In principle, such actions could potentiate the renewal of high-amplitude pulses of GH in androgen-replete individuals...
  60. ncbi Noninvasive in vivo investigative probes of adaptive mechanisms of neuroendocrine regulation: the paradigm of the hypothalamo-pituitary-gonadal axis in the aging male
    J D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, MN 55905, USA
    J Endocrinol Invest 26:2-14. 2003
    ..The aging male gonadal axis provides a well studied paradigmatic platform to illustrate the formulation and implementation of analytical strategies in diverse systems...
  61. ncbi Estradiol supplementation in postmenopausal women doubles rebound-like release of growth hormone (GH) triggered by sequential infusion and withdrawal of somatostatin: evidence that estrogen facilitates endogenous GH-releasing hormone drive
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 89:121-7. 2004
    ..Accordingly, we hypothesize that estradiol stimulates pulsatile GH secretion, at least in part, by enhancing the release and/or action of hypothalamic GHRH...
  62. ncbi Human GH pulsatility: an ensemble property regulated by age and gender
    J D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical School of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, MN 55905, USA
    J Endocrinol Invest 26:799-813. 2003
    ..This unifying platform offers a convergent perspective of multivalent control of GH outflow...
  63. ncbi Sustained growth hormone (GH) and insulin-like growth factor I responses to prolonged high-dose twice-daily GH-releasing hormone stimulation in middle-aged and older men
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 89:6325-30. 2004
    ....
  64. ncbi Neuroendocrine facets of human puberty
    Johannes D Veldhuis
    University of Virginia School of Medicine, Charlottesville, USA
    Neurobiol Aging 24:S93-S119; discussion S121-2. 2003
    ..Most notably, the outflow of gonadotropins and growth hormone (GH) proceeds both independently and jointly. The current update highlights this unique dependency in the human...
  65. ncbi Age and secretagogue type jointly determine dynamic growth hormone responses to exogenous insulin-like growth factor-negative feedback in healthy men
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 89:5542-8. 2004
    ....
  66. ncbi Testosterone blunts feedback inhibition of growth hormone secretion by experimentally elevated insulin-like growth factor-I concentrations
    Johannes D Veldhuis
    Endocrine Research Unit, Mayo School of Graduate Medical Education, General Clinical Research Center, 200 First Street Southwest, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 90:1613-7. 2005
    ..Both effects of Te differ from those reported recently for estradiol in postmenopausal women. Accordingly, we postulate that Te and estrogen modulate IGF-I negative feedback differentially...
  67. ncbi Mechanisms of ensemble failure of the male gonadal axis in aging
    J D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, MN 55905, USA
    J Endocrinol Invest 28:8-13. 2005
    ..The most proximate locus of impairment is not yet known...
  68. ncbi Three-peptide control of pulsatile and entropic feedback-sensitive modes of growth hormone secretion: modulation by estrogen and aromatizable androgen
    Johannes D Veldhuis
    Mayo Clinic and Graduate School of Medicine, Division of Endocrinology and Metabolism, Department of Internal Medicine, Rochester, MN 55905, USA
    J Pediatr Endocrinol Metab 16:587-605. 2003
    ..The dynamic interactions in this three-peptide network, rather than the activity of any single effector, subserve core adaptations in GH secretion across development...
  69. ncbi Gender modulates sequential suppression and recovery of pulsatile growth hormone secretion by physiological feedback signals in young adults
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 90:2874-81. 2005
    ..A frugal but sufficient explanation of the ensemble outcomes is that women sustain greater hypothalamo-pituitary agonist input than men...
  70. ncbi Endocrine control of body composition in infancy, childhood, and puberty
    Johannes D Veldhuis
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    Endocr Rev 26:114-46. 2005
    ..The present critical review examines hormonal regulation of body composition in infancy, childhood, and puberty...
  71. ncbi Joint mechanisms of impaired growth-hormone pulse renewal in aging men
    Johannes D Veldhuis
    Endocrine Research Unit, Department of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 90:4177-83. 2005
    ..Experimental data indicate that high-amplitude GH pulses are evoked by reversible cycles of GH-induced negative feedback. Whether aging impairs autofeedback is unknown...
  72. ncbi Oscillations in joint synchrony of reproductive hormones in healthy men
    Xin Wang
    Endocrine Research Unit, Mayo Clinic, Rochester, Minnesota 55905, USA
    Am J Physiol Endocrinol Metab 301:E1163-73. 2011
    ....
  73. ncbi Pre- versus postmenopausal age, estradiol, and peptide-secretagogue type determine pulsatile growth hormone secretion in healthy women: studies using submaximal agonist drive and an estrogen clamp
    Susan B Hudson
    Department of Obstetrics and Gynecology, Mayo School of Graduate Medical Education, Clinical Translational Research Center, Mayo Clinic, Rochester, Minnesota 55905
    J Clin Endocrinol Metab 95:353-60. 2010
    ..GH-releasing peptide (GHRP), GHRH, and somatostatin are physiological regulators of pulsatile GH secretion...
  74. ncbi Short-term testosterone supplementation does not activate GH and IGF-I production in postmenopausal women
    Cacia Soares-Welch
    Endocrine Research Unit, Department of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, MN 55905, USA
    Clin Endocrinol (Oxf) 63:32-8. 2005
    ....
  75. ncbi Aging in healthy men impairs recombinant human luteinizing hormone (LH)-stimulated testosterone secretion monitored under a two-day intravenous pulsatile LH clamp
    Peter Y Liu
    Endocrine Research Unit, Department of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 90:5544-50. 2005
    ..These findings do not exclude concomitant defects in GnRH outflow and/or Te-negative feedback in the aging male...
  76. ncbi Pituitary and/or peripheral estrogen-receptor alpha regulates follicle-stimulating hormone secretion, whereas central estrogenic pathways direct growth hormone and prolactin secretion in postmenopausal women
    Mihaela Cosma
    Endocrine Research Unit, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, 200 First Street S W, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 93:951-8. 2008
    ..Estradiol (E(2)) stimulates GH and prolactin secretion and suppresses FSH secretion in postmenopausal women. Whether central nervous system (CNS) or pituitary mechanisms (or both) mediate such actions is not known...
  77. ncbi Estrogen supplementation selectively enhances hypothalamo-pituitary sensitivity to ghrelin in postmenopausal women
    Petra Kok
    Department of Internal Medicine, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 93:4020-6. 2008
    ..The hypothesis is relevant to understanding the basis of hyposomatotropism in aging and other relatively hypogonadal states...
  78. ncbi Sustained elevation of pulsatile growth hormone (GH) secretion and insulin-like growth factor I (IGF-I), IGF-binding protein-3 (IGFBP-3), and IGFBP-5 concentrations during 30-day continuous subcutaneous infusion of GH-releasing peptide-2 in older men and
    Cyril Y Bowers
    Tulane University Health Sciences Center, New Orleans, Louisiana 70112, USA
    J Clin Endocrinol Metab 89:2290-300. 2004
    ..We conclude that age, gender, stimulus duration, and secretagogue combination determine acute, intermediate, and extended responses of the somatotropic axis in the older adult...
  79. ncbi Age-specific changes in the regulation of LH-dependent testosterone secretion: assessing responsiveness to varying endogenous gonadotropin output in normal men
    Peter Y Liu
    Endocrine Research Unit, Dept. of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Regul Integr Comp Physiol 289:R721-8. 2005
    ..The experimental strategy of graded suppression of neuroglandular outflow may have utility in estimating dose-response adaptations in other endocrine systems...
  80. ncbi The role of falling leptin levels in the neuroendocrine and metabolic adaptation to short-term starvation in healthy men
    Jean L Chan
    Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA
    J Clin Invest 111:1409-21. 2003
    ..The role of leptin in normalizing several starvation-induced neuroendocrine changes may have important implications for the pathophysiology and treatment of eating disorders and obesity...
  81. ncbi Single and combined effects of growth hormone and testosterone administration on measures of body composition, physical performance, mood, sexual function, bone turnover, and muscle gene expression in healthy older men
    Kimberly T Brill
    Department of Internal Medicine, University of Virginia, Charlottesville, Virginia 22908, USA
    J Clin Endocrinol Metab 87:5649-57. 2002
    ..We conclude that 1 month of GH and/or T administration improves certain measures of balance and physical performance in older men and increases muscle IGF-I gene expression...
  82. ncbi Age attenuates testosterone secretion driven by amplitude-varying pulses of recombinant human luteinizing hormone during acute gonadotrope inhibition in healthy men
    Paul Y Takahashi
    Endocrine Research Unit, Department of Internal Medicine, General Clinical Research Center, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 92:3626-32. 2007
    ..Whether testosterone (Te) depletion in aging men reflects deficits in the testis, hypothalamus, and/or pituitary gland is unknown...
  83. ncbi Secretagogue type, sex-steroid milieu, and abdominal visceral adiposity individually determine secretagogue-stimulated cortisol secretion
    Ali Iranmanesh
    Endocrine Section, Department of Medicine, Salem Veterans Affairs Medical Center, Salem, Virginia 24153, USA
    Eur J Endocrinol 162:1043-9. 2010
    ....
  84. ncbi Aging attenuates both the regularity and joint synchrony of LH and testosterone secretion in normal men: analyses via a model of graded GnRH receptor blockade
    Peter Y Liu
    Endocrine Research Unit, Dept. of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, MN 55905, USA
    Am J Physiol Endocrinol Metab 290:E34-E41. 2006
    ..Thus the experimental strategy of stepwise silencing of an agonistic pathway may have utility in dissecting the bases of altered neurohormonal linkages in other systems...
  85. ncbi Amplified and orderly growth hormone secretion characterizes lean adolescents with polycystic ovary syndrome
    Maria C Garcia-Rudaz
    Centro de Investigaciones Endocrinologicas CEDIE, Hospital de Niños R Gutiérrez, Buenos Aires, Argentina
    Eur J Endocrinol 147:207-16. 2002
    ..The present study evaluated the hypothesis that pulsatile GH secretion is altered in adolescents with polycystic ovary syndrome (PCOS)...
  86. ncbi Estrogen elevates the peak overnight production rate of acylated ghrelin
    Remberto C Paulo
    Department of Pediatrics, Endocrine Research Unit, Clinical Translational Research Center, Mayo Medical and Graduate Schools, Mayo Clinic, Rochester, Minnesota 55901, USA
    J Clin Endocrinol Metab 93:4440-7. 2008
    ..Acylated ghrelin is the putatively bioactive GH secretagogue...
  87. ncbi Divergent gonadotropin-gonadal dose-responsive coupling in healthy young and aging men
    Daniel M Keenan
    Division of Endocrinology and Metabolism, Dept. of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, 200 First St. SW, Rochester, MN 55905, USA
    Am J Physiol Regul Integr Comp Physiol 286:R381-9. 2004
    ..On the basis of these data, we postulate that aging in the human male alters specific dose-response attributes linking LH con and Te sec and disrupts the time waveform of LH and Te sec bursts...
  88. ncbi Age in men does not determine gonadotropin-releasing hormone's dose-dependent stimulation of luteinizing hormone secretion under an exogenous testosterone clamp
    Ali Iranmanesh
    Endocrine Section, Department of Medicine, Salem Veterans Affairs Medical Center, Salem, Virginia 24153, USA
    J Clin Endocrinol Metab 95:2877-84. 2010
    ..Aging is associated with a decline in incremental LH pulse amplitude, which could be due to decreased GnRH secretion or impaired GnRH action...
  89. ncbi Analysis of bidirectional pattern synchrony of concentration-secretion pairs: implementation in the human testicular and adrenal axes
    Peter Y Liu
    Division of Endocrinology, Department of Internal Medicine, Endocrine Research Unit and General Clinical Research Center, Mayo Clinic, Mayo Medical and Graduate Schools of Medicine, Rochester, MN 55905, USA
    Am J Physiol Regul Integr Comp Physiol 288:R440-6. 2005
    ..The linking of relevant biological input to output signals and vice versa should be useful in the dissection of the reciprocal control of neuroendocrine systems or even in the analysis of other nonendocrine networks...
  90. ncbi Hypocortisolemic clamp unmasks jointly feedforward- and feedback-dependent control of overnight ACTH secretion
    Ali Iranmanesh
    Department of Medicine, Salem Veterans Affairs Medical Center, Salem, Virginia 24153, USA
    Eur J Endocrinol 159:561-8. 2008
    ..ACTH secretion is under hypothalamic stimulatory (feedforward) and adrenal inhibitory (feedback) control...
  91. ncbi Dual secretagogue drive of burst-like growth hormone secretion in postmenopausal compared with premenopausal women studied under an experimental estradiol clamp
    Dana Erickson
    Division of Endocrinology and Metabolism, Department of Internal Medicine, Mayo Medical and Graduate Schools of Medicine, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 89:4746-54. 2004
    ....
  92. ncbi Determinants of dual secretagogue drive of burst-like growth hormone secretion in premenopausal women studied under a selective estradiol clamp
    Dana Erickson
    Endocrine Research Unit, Department of Internal Medicine, Mayo School of Graduate Medical Education, General Clinical Research Center, Mayo Clinic, Rochester, Minnesota 55905, USA
    J Clin Endocrinol Metab 90:1741-51. 2005
    ..Moreover, the rapidity of GH release is controlled 2-fold jointly by E(2) and GHRH...
  93. ncbi Effects of continuous versus intermittent exercise, obesity, and gender on growth hormone secretion
    Arthur Weltman
    Department of Human Services, University of Virginia, Charlottesville, Virginia 22904, USA
    J Clin Endocrinol Metab 93:4711-20. 2008
    ..Obese individuals often have low fitness levels, limiting their ability to complete a typical 30-min bout of continuous exercise. An alternative regimen in obese subjects may be shorter bouts of exercise interspersed throughout the day...
  94. ncbi Putative somatostatin suppression potentiates adrenocorticotropin secretion driven by ghrelin and human corticotropin-releasing hormone
    Ali Iranmanesh
    Endocrine Section, Department of Medicine, Salem Veterans Affairs Medical Center, Salem, Virginia 24153, USA
    J Clin Endocrinol Metab 92:3653-9. 2007
    ..In principle, actions of these agonists could be subject to inhibitory modulation by hypothalamic somatostatin (SS)...
  95. ncbi Sex defines the age dependence of endogenous ACTH-cortisol dose responsiveness
    Daniel M Keenan
    Department of Statistics, University of Virginia, Charlottesville, Virginia, USA
    Am J Physiol Regul Integr Comp Physiol 297:R515-23. 2009
    ..34, P = 0.0085). These outcomes demonstrate that sex, age, and BMI modulate selective properties of endogenous ACTH-cortisol drive in humans, thereby indicating the need to control these three major variables in experimental comparisons...
  96. ncbi Age-dependent regression analysis of male gonadal axis
    Daniel M Keenan
    Department of Statistics, University of Virginia, Charlottesville, Virginia, USA
    Am J Physiol Regul Integr Comp Physiol 297:R1215-27. 2009
    ..The analytical formalism should be generalizable to other ensemble regulatory systems, such as those that control growth, reproduction, stress adaptations, and glucose metabolism...
  97. ncbi Deterministic construct of amplifying actions of ghrelin on pulsatile growth hormone secretion
    Leon S Farhy
    Division of Endocrinology and Metabolism, Department of Internal Medicine, School of Medicine, University of Virginia, Charlottesville, USA
    Am J Physiol Regul Integr Comp Physiol 288:R1649-63. 2005
    ..The minimal construct of GHS-GHRH-SRIF-GH interactions should aid in integrating physiological data, testing regulatory hypotheses, and forecasting innovative experiments...
  98. ncbi Physiological and pharmacological regulation of 20-kDa growth hormone
    Kin Chuen Leung
    Pituitary Research Unit, Garvan Institute of Medical Research, St Vincent s Hospital, Sydney, New South Wales 2010, Australia
    Am J Physiol Endocrinol Metab 283:E836-43. 2002
    ..The 20-kDa GH level is reduced by administration of exogenous 22-kDa GH, suggesting rapid negative feedback regulation on pituitary release...
  99. ncbi GH secretory pattern in young adults who discontinued GH treatment for GH deficiency and decreased longitudinal growth in childhood
    Johan Svensson
    Research Centre for Endocrinology and Metabolism, Sahlgrenska University Hospital, Goteborg, Sweden
    Eur J Endocrinol 155:91-9. 2006
    ..Sixteen matched healthy controls were also studied. All blood samples were analysed using an ultrasensitive GH assay and then, approximate entropy (ApEn) and deconvolution analysis were performed...
  100. ncbi Pioglitazone treatment increases spontaneous growth hormone (GH) secretion and stimulated GH levels in polycystic ovary syndrome
    Dorte Glintborg
    Department of Endocrinology and Metabolism, Odense University Hospital, Denmark
    J Clin Endocrinol Metab 90:5605-12. 2005
    ..GH acts as an important ovarian cogonadotropin, and GH disturbances may be an additional pathogenic factor in PCOS. Decreased abdominal fat mass and improved insulin sensitivity during pioglitazone treatment may affect GH secretion...
  101. ncbi Unequal autonegative feedback by GH models the sexual dimorphism in GH secretory dynamics
    Leon S Farhy
    Division of Endocrinology and Metabolism, Department of Internal Medicine, The University of Virginia Health System, Charlottesville, Virginia 22908, USA
    Am J Physiol Regul Integr Comp Physiol 282:R753-64. 2002
    ..3-h-interval, multiphasic, volleylike male GH pattern into a femalelike profile with irregular pulses of higher frequency...

Research Grants57

  1. Age-Dependent Estrogen-Independent Mechanism of Hyposomatotropism in Women
    Johannes D Veldhuis; Fiscal Year: 2010
    ..Therefore, this proposal seeks to unravel fundamental mechanisms that control the production of the major trophic hormones GH and IGF-I, which maintain bone and muscle mass, reduce abdominal fat and enhance quality of life. ..
  2. Analytical Reconstruction of Feedback Signaling in Aging Men
    Johannes Veldhuis; Fiscal Year: 2007
    ..The present proposal develops a general biomathematical framework for dissecting otherwise observed pathways that control hormone output in aging, stress and disease. ..
  3. ACTIONS OF TESTOSTERONE ON THE AGING MALE GH AXIS
    Johannes Veldhuis; Fiscal Year: 2007
    ..g., for urological cancers) that markedly reduce male hormone concentrations. ..
  4. ACTIONS OF ESTROGEN IN MATURING GRAAFIAN FOLLICLES
    Johannes Veldhuis; Fiscal Year: 2005
    ..Understanding such fundamental interactions is important to the rational design of alternative strategies to interrupt normal and rescue impaired steroidogenesis in the maturing Graafian follicle and corpus luteum. ..
  5. THE AGING GH AXIS IN POSTMENOPAUSAL WOMEN
    Johannes Veldhuis; Fiscal Year: 2005
    ..An enhanced knowledge base should aid ultimately in formulating more innovative preventive and interventional strategies to limit hyposomatotropism in older and/or estrogen-deficient humans. ..
  6. ENSEMBLE MODEL OF STRESS ACTH-ADRENAL AXIS
    Johannes Veldhuis; Fiscal Year: 2005
    ....
  7. Novel Active Repressor Model of Human LDL-Receptor Regulation
    Johannes Veldhuis; Fiscal Year: 2007
    ..If so, targeting this gene product could potentially shift cholesterol accumulation away from arteries toward the liver. This would represent a new treatment approach for patients with atherosclerotic disease. ..
  8. Mechanistic bases for age-related androgen deficiency
    Johannes Veldhuis; Fiscal Year: 2007
    ..Knowing why testosterone falls should help foster new and safer ways to prevent the problem. ..
  9. Aging Systems in Geriatrics: the Male Gonadal Axis
    Johannes D Veldhuis; Fiscal Year: 2010
    ..Why or how the decline occurs is not known. This grant studies mechanisms in the brain, pituitary (master) gland and testis (male gonad), which begin to fail in aging men under stress. ..
  10. Ensemble Control of ACTH Secretion: Impact of Gender
    Johannes D Veldhuis; Fiscal Year: 2010
    ..The goal is to unveil new ways to detect, prevent and treat abnormal stress-adaptive responses in aging, illness and disease. ..
  11. Age-Dependent Estrogen-Independent Mechanism of Hyposomatotropism in Women
    Johannes Veldhuis; Fiscal Year: 2009
    ..Therefore, this proposal seeks to unravel fundamental mechanisms that control the production of the major trophic hormones GH and IGF-I, which maintain bone and muscle mass, reduce abdominal fat and enhance quality of life. ..
  12. Ensemble Control of ACTH Secretion: Impact of Gender
    Johannes Veldhuis; Fiscal Year: 2009
    ..The goal is to unveil new ways to detect, prevent and treat abnormal stress-adaptive responses in aging, illness and disease. ..
  13. Age-Dependent Estrogen-Independent Mechanism of Hyposomatotropism in Women
    Johannes Veldhuis; Fiscal Year: 2007
    ..Therefore, this proposal seeks to unravel fundamental mechanisms that control the production of the major trophic hormones GH and IGF-I, which maintain bone and muscle mass, reduce abdominal fat and enhance quality of life. ..
  14. Ensemble Control of ACTH Secretion: Impact of Gender
    Johannes Veldhuis; Fiscal Year: 2007
    ..The goal is to unveil new ways to detect, prevent and treat abnormal stress-adaptive responses in aging, illness and disease. ..
  15. Ensemble Disruption of the GnRH-LH-Testosterone Axis
    Johannes Veldhuis; Fiscal Year: 2007
    ..Expected corollary outcomes are enhanced diagnosis, assessment and management of more subtle pathophysiology of the male gonadal axis in puberty and adulthood. ..
  16. ACTIONS OF ESTROGEN IN MATURING GRAAFIAN FOLLICLES
    Johannes Veldhuis; Fiscal Year: 2001
    ....
  17. AGING GH AXIS IN POSTMENOPAUSAL WOMEN
    Johannes Veldhuis; Fiscal Year: 2000
    ..Such knowledge has significant clinical implications to rational estrogen-replacement strategies in older women with estrogen-deficiency states and physical frailty accompanied by relative hyposomatotropism. ..
  18. ACTIONS OF ESTROGEN IN MATURING GRAAFIAN FOLLICLES
    Johannes Veldhuis; Fiscal Year: 1993
    ..The preceding studies should contribute important new insights into and further developments in fertility regulation in man, domestic animals, and endangered wild species...
  19. ACTIONS OF ESTROGEN IN MATURING GRAAFIAN FOLLICLES
    Johannes Veldhuis; Fiscal Year: 1990
    ..Accordingly, these investigations are likely to contribute to new approaches to fertility regulation in the human, domestic animal or endangered wild species...