Research Topics
| R GruetterSummaryAffiliation: University of Minnesota Country: USA Publications
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Detail Information
Publications
A mathematical model of compartmentalized neurotransmitter metabolism in the human brainR Gruetter
Department of Radiology, Center for Magnetic Resonance Research and General Clinical Research Center, University of Minnesota, Minneapolis, Minnesota 55455, USA
Am J Physiol Endocrinol Metab 281:E100-12. 2001..The study underlines the importance of assumptions made in modeling 13C labeling data in brain...- In vivo 13C NMR studies of compartmentalized cerebral carbohydrate metabolismRolf Gruetter
Department of Radiology, Center for MR Research, University of Minnesota, 2021 6th Street SE, Minneapolis, MN 55455, USA
Neurochem Int 41:143-54. 2002.... - Glycogen: the forgotten cerebral energy storeRolf Gruetter
Departments of Radiology and Neuroscience, University of Minnesota, Minneapolis, Minnesota, USA
J Neurosci Res 74:179-83. 2003.... 
Localized in vivo 13C NMR spectroscopy of the brainRolf Gruetter
Department of Radiology, Center for MR Research, University of Minnesota, 2021 6th Street SE, Minneapolis, MN 55455, USA
NMR Biomed 16:313-38. 2003..We conclude that the unique and novel insights provided by (13)C NMR spectroscopy have opened many new research areas that are likely to improve the understanding of brain carbohydrate metabolism in health and disease...- Field mapping without reference scan using asymmetric echo-planar techniquesR Gruetter
Department of Radiology, University of Minnesota, Minneapolis, USA
Magn Reson Med 43:319-23. 2000..1 Hz. With adiabatic low flip-angle excitation, the time required for field mapping was below 1 second... - In vivo effect of chronic hypoxia on the neurochemical profile of the developing rat hippocampusLakshmi Raman
Department of Pediatrics, University of Minnesota, Minneapolis, MN 55455, USA
Brain Res Dev Brain Res 156:202-9. 2005..The altered hippocampal neurochemistry during its development may underlie some of the cognitive deficits present in human infants at risk of chronic hypoxia... - Localized in vivo 13C-NMR of glutamate metabolism in the human brain: initial results at 4 teslaR Gruetter
Departments of Radiology, Medicine, Psychiatry and Biochemistry, University of Minnesota, Minneapolis, Minn, USA
Dev Neurosci 20:380-8. 1998.... - In vivo measurements of brain glucose transport using the reversible Michaelis-Menten model and simultaneous measurements of cerebral blood flow changes during hypoglycemiaI Y Choi
Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota Medical School, Minneapolis 55455, USA
J Cereb Blood Flow Metab 21:653-63. 2001..At this point, CBF increased sharply by 57% +/- 22%, suggesting that brain glucose concentration is the signal that triggers defense mechanisms aimed at improving glucose delivery to the brain during hypoglycemia... - Neuroglial metabolism in the awake rat brain: CO2 fixation increases with brain activityGULIN OZ
Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota 55455, USA
J Neurosci 24:11273-9. 2004..We postulate that the high rate of anaplerosis in awake brain is linked to brain activity by maintaining glial glutamine concentrations during increased neurotransmission... - Study of tricarboxylic acid cycle flux changes in human visual cortex during hemifield visual stimulation using (1)H-[(13)C] MRS and fMRIW Chen
Center for Magnetic Resonance Research, Radiology Department, University of Minnesota School of Medicine, Minneapolis, Minnesota 55455, USA
Magn Reson Med 45:349-55. 2001..Magn Reson Med 45:349-355, 2001... - The effect of insulin on in vivo cerebral glucose concentrations and rates of glucose transport/metabolism in humansE R Seaquist
Department of Medicine, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA
Diabetes 50:2203-9. 2001..These data support the hypothesis that the majority of cerebral glucose uptake/metabolism is an insulin-independent process in humans... - Metabolic changes in quinolinic acid-lesioned rat striatum detected non-invasively by in vivo (1)H NMR spectroscopyI Tkac
Department of Radiology, University of Minnesota, 2021 6th Street SE, Minneapolis, MN 55455, USA
J Neurosci Res 66:891-8. 2001.... - In vivo 1H NMR spectroscopy of the human brain at 7 TI Tkac
Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota 55455, USA
Magn Reson Med 46:451-6. 2001..Characteristic spectral patterns of metabolites, e.g., myo-inositol and taurine, were discernible in the in vivo spectra, which facilitated an unambiguous signal assignment... - Detecting natural abundance carbon signal of NAA metabolite within 12-cm3 localized volume of human brain using 1H-[13C] NMR spectroscopyW Chen
Radiology Department, University of Minnesota, School of Medicine, Minneapolis 55455, USA
Magn Reson Med 40:180-4. 1998.... - Measurement of reduced glutathione (GSH) in human brain using LCModel analysis of difference-edited spectraMelissa Terpstra
University of Minnesota, Department of Radiology, Center for MR Research Minneapolis, Minnesota
Magn Reson Med 50:19-23. 2003..GSH concentration was estimated from the in vivo spectra as 1.3 +/- 0.2 micro mol/g (mean +/- SD, n = 12)... - In vivo 1H NMR spectroscopy of rat brain at 1 ms echo timeI Tkac
Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis 55455, USA
Magn Reson Med 41:649-56. 1999..At 9.4 T, peaks close to the water were observed, including the H-1 of alpha-D-glucose at 5.23 ppm and a tentative H-1 resonance of glycogen at 5.35 ppm... - Assessment of adrenoleukodystrophy lesions by high field MRS in non-sedated pediatric patientsG Oz
Center for MR Research, University of Minnesota, Minneapolis, MN 55455, USA
Neurology 64:434-41. 2005.... - Human brain glycogen content and metabolism: implications on its role in brain energy metabolismGULIN OZ
Department of Radiology, Center for MR Research, University of Minnesota, 2021 6th St SE, Minneapolis, MN 55455, USA
Am J Physiol Endocrinol Metab 292:E946-51. 2007..We conclude that the brain stores a substantial amount of glycogen relative to free glucose and metabolizes this store very slowly under normal physiology... - Neurochemical changes in the developing rat hippocampus during prolonged hypoglycemiaRaghavendra Rao
Division of Neonatology, Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota, USA
J Neurochem 114:728-38. 2010..Compensatory neurochemical changes maintain energy homeostasis during prolonged hypoglycemia in the developing hippocampus... - Brain glucose concentrations in poorly controlled diabetes mellitus as measured by high-field magnetic resonance spectroscopyElizabeth R Seaquist
Department of Medicine, University of Minnesota Medical School, MN 55455, USA
Metabolism 54:1008-13. 2005..1 micromol/g wet wt; P = .1). Our sample size gave 80% power to detect a difference as small as 1.1 micromol/g wet wt. We conclude that chronic hyperglycemia in diabetes does not alter brain glucose concentrations in human subjects... - In vivo 1H NMR spectroscopy of the human brain at high magnetic fields: metabolite quantification at 4T vs. 7TIvan Tkac
Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota 55455, USA
Magn Reson Med 62:868-79. 2009.... - Validation of glutathione quantitation from STEAM spectra against edited 1H NMR spectroscopy at 4T: application to schizophreniaMelissa Terpstra
Center for Magnetic Resonance Research, Department of Radiology, University of MN, Minneapolis, MN 55455, USA
MAGMA 18:276-82. 2005..A secondary objective was to compare several of the neurochemical concentrations quantified along with GSH using LCModel analysis of short echo time spectra in schizophrenia versus control... - Proton-observed carbon-edited NMR spectroscopy in strongly coupled second-order spin systemsPierre Gilles Henry
Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota Medical School, Minneapolis, Minnesota, USA
Magn Reson Med 55:250-7. 2006..This effect is demonstrated theoretically with density matrix calculations and simulations, and experimentally with measured POCE spectra of [3-13C]glutamate... - Proton MRS of the unilateral substantia nigra in the human brain at 4 tesla: detection of high GABA concentrationsGULIN OZ
Center for MR Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota 55455, USA
Magn Reson Med 55:296-301. 2006..These findings establish the feasibility of obtaining a neurochemical profile of the unilateral human SN by single-voxel spectroscopy in small volumes... - Biochemical quantification of total brain glycogen concentration in rats under different glycemic statesFlorence D Morgenthaler
Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, USA
Neurochem Int 48:616-22. 2006..Finally we also conclude that previous interpretation of (13)C NMR spectroscopy data accurately reflected the changes in total brain glycogen content... - Quantification of vitamin C in the rat brain in vivo using short echo-time 1H MRSMelissa Terpstra
Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota 55455, USA
Magn Reson Med 55:979-83. 2006..Ascorbate concentrations measured using STEAM decreased with increasing postnatal rat age, in agreement with published brain ascorbate concentrations measured in vitro using high-performance liquid chromatography (HPLC)... 
Editing through multiple bonds: threonine detectionMalgorzata Marjanska
Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, Minneapolis, MN 55455, USA
Magn Reson Med 59:245-51. 2008..A threonine concentration was estimated at 0.8 +/- 0.3 mM (mean +/- SD, n = 6) in the rat brain and at approximately 0.33 mM in the human brain...- Sensitivity of single-voxel 1H-MRS in investigating the metabolism of the activated human visual cortex at 7 TSilvia Mangia
Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN 55455, USA
Magn Reson Imaging 24:343-8. 2006..Quantification of metabolites was, in general, not affected beyond 1% by line-width changes within 0.5 Hz... - In vivo 13C NMR spectroscopy and metabolic modeling in the brain: a practical perspectivePierre Gilles Henry
Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA
Magn Reson Imaging 24:527-39. 2006..The present work reviews the ingredients necessary for a dynamic metabolic modeling study, with particular emphasis on practical issues... - Dynamics of lactate concentration and blood oxygen level-dependent effect in the human visual cortex during repeated identical stimuliSilvia Mangia
Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, MN 55455, USA
J Neurosci Res 85:3340-6. 2007..Alternative possibilities that could account for an adaptation of [Lac] changes are also discussed... - Perinatal iron deficiency predisposes the developing rat hippocampus to greater injury from mild to moderate hypoxia-ischemiaRaghavendra Rao
Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota 55455, USA
J Cereb Blood Flow Metab 27:729-40. 2007.... - Brain energy metabolism and neurotransmission at near-freezing temperatures: in vivo (1)H MRS study of a hibernating mammalPierre Gilles Henry
Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA
J Neurochem 101:1505-15. 2007.... - Sustained neuronal activation raises oxidative metabolism to a new steady-state level: evidence from 1H NMR spectroscopy in the human visual cortexSilvia Mangia
Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota 55455, USA
J Cereb Blood Flow Metab 27:1055-63. 2007.... - Detection of an antioxidant profile in the human brain in vivo via double editing with MEGA-PRESSMelissa Terpstra
Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota 55455, USA
Magn Reson Med 56:1192-9. 2006..GSSG contributions to the DEW MEGA-PRESS GSH resonance (3.0 ppm) are negligible under physiologic conditions, and would be evidenced by a distinct GSSG resonance (3.3 ppm) at exceptionally high concentrations... - Uncovering hidden in vivo resonances using editing based on localized TOCSYMalgorzata Marjanska
Center for Magnetic Resonance Research and Department of Radiology, University of Minnesota, 2021 6th Street SE, Minneapolis, MN 55455, USA
Magn Reson Med 53:783-9. 2005..63 ppm from under water and the lactate methyl resonances from beneath a strong lipid signal. The method can be extended to further spin systems where conventional editing methods are difficult to perform... - Brain glucose concentrations in patients with type 1 diabetes and hypoglycemia unawarenessAmy B Criego
Department of Pediatrics, University of Minnesota Medical School, 420 Delaware Street SE, Minneapolis, MN 55455, USA
J Neurosci Res 79:42-7. 2005..5 +/- 0.3 vs. 4.7 +/- 0.1 micromol/g wet weight, P = 0.016). These data suggest that changes in brain glucose transport or metabolism may occur as a result of recurrent hypoglycemia... - Developmental and regional changes in the neurochemical profile of the rat brain determined by in vivo 1H NMR spectroscopyIvan Tkac
Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota 55455, USA
Magn Reson Med 50:24-32. 2003..The current data may serve as a reference for studies focused on developmental defects and pathologies using neonatal rat models... - Perinatal iron deficiency alters the neurochemical profile of the developing rat hippocampusRaghavendra Rao
Department of Pediatrics, University of Minnesota, Minneapolis, MN 55455, USA
J Nutr 133:3215-21. 2003..An altered neurochemical profile of the developing hippocampus may underlie some of the cognitive deficits observed in human infants with perinatal iron deficiency... - Toward dynamic isotopomer analysis in the rat brain in vivo: automatic quantitation of 13C NMR spectra using LCModelPierre Gilles Henry
Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, 2021 6th Street SE, Minneapolis, MN 55455, USA
NMR Biomed 16:400-12. 2003..The possibility of measuring in vivo a wealth of information that was hitherto accessible only in extracts is likely to expand the scope of metabolic studies in the intact brain... - Ultrahigh field magnetic resonance imaging and spectroscopyKamil Ugurbil
Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, MN 55455, USA
Magn Reson Imaging 21:1263-81. 2003 - 1H NMR detection of vitamin C in human brain in vivoMelissa Terpstra
Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota 55455, USA
Magn Reson Med 51:225-9. 2004..This study represents the first in vivo detection of vitamin C in the human brain using 1H MRS. A concentration of 1.3 +/- 0.3 micromol/g (mean +/- SD, N = 4) was estimated... - Highly resolved in vivo 1H NMR spectroscopy of the mouse brain at 9.4 TIvan Tkac
Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis 55455, USA
Magn Reson Med 52:478-84. 2004..4 T can provide precise biochemical information from distinct regions of the mouse brain noninvasively that can be used for monitoring of disease progression and treatment as well as phenotyping in transgenic mice models... - Elucidation of the role of fructose 2,6-bisphosphate in the regulation of glucose fluxes in mice using in vivo (13)C NMR measurements of hepatic carbohydrate metabolismIn-Young Choi
Departments of RadiologyBiochemistry, Molecular Biology and Biophysics Neuroscience University of Minnesota Medical School, Minneapolis, MN 55455, USA
Eur J Biochem 269:4418-26. 2002..These observations provide a key to understanding the mechanisms by which elevated hepatic Fru-2,6-P2 levels promote reduced hepatic glucose production and lower blood glucose in diabetes mellitus... - Effect of deep pentobarbital anesthesia on neurotransmitter metabolism in vivo: on the correlation of total glucose consumption with glutamatergic actionIn-Young Choi
Department of Radiology, University of Minnesota, Center for MR Research, Minneapolis 55455, USA
J Cereb Blood Flow Metab 22:1343-51. 2002..However, the rates of cerebral oxidative glucose metabolism and glutamatergic neurotransmission, CMRglc(ox)/V(NT), did not correlate with a 1:1 stoichiometry... - Brain glucose concentrations in healthy humans subjected to recurrent hypoglycemiaAmy B Criego
Department of Pediatrics, University of Minnesota Medical School, Minneapolis, USA
J Neurosci Res 82:525-30. 2005..1 +/- 0.8 vs. 4.5 +/- 0.5 mumol/g wet weight, respectively, P = 0.05). These observations suggest that brain glucose transport or metabolism is not altered following short episodes of recurrent hypoglycemia in healthy human volunteers... - Effect of chronic hypoglycaemia on glucose concentration and glycogen content in rat brain: A localized 13C NMR studyHongxia Lei
Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA
J Neurochem 99:260-8. 2006..Such increased brain glucose concentrations can result in a lowered glycaemic threshold of counter-regulation observed in chronic hypoglycaemia... - Direct validation of in vivo localized 13C MRS measurements of brain glycogenHongxia Lei
Department of Radiology, University of Minnesota, Minneapolis, Minnesota, USA
Magn Reson Med 57:243-8. 2007..79). The results are consistent with the notion that localized 13C MRS measurements closely reflect 13C glycogen content in the brain... - Effect of hypoglycemia on brain glycogen metabolism in vivoIn-Young Choi
Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA
J Neurosci Res 72:25-32. 2003.... - Brain glycogen: an insulin-sensitive carbohydrate storeE R Seaquist
Department of Medicine, University of Minnesota, USA
Diabetes Nutr Metab 15:285-9; discussion 289-90. 2002 - Water diffusion in rat brain in vivo as detected at very large b values is multicompartmentalJ Pfeuffer
Department of Radiology, University of Minnesota Medical School, Center for Magnetic Resonance Research, Minneapolis 55455, USA
MAGMA 8:98-108. 1999..e. the relative volume fractions and the extracellular tortuosity, while the intrinsic intracellular diffusion constant and the exchange time are predicted to have minor influence... - Direct, noninvasive measurement of brain glycogen metabolism in humansGULIN OZ
Department of Radiology, Center for MR Research, University of Minnesota, 2021 6th St S E, Minneapolis, MN 55455, USA
Neurochem Int 43:323-9. 2003..The noninvasive detection of human brain glycogen opens the prospect of understanding the role and function of this important energy reserve under various physiological and pathophysiological conditions... - Direct in vivo measurement of human cerebral GABA concentration using MEGA-editing at 7 TeslaMelissa Terpstra
Center for MR Research, Department of Radiology, University of Minnesota, Minneapolis, Minnesota 55455, USA
Magn Reson Med 47:1009-12. 2002.... - In vivo 13C NMR assessment of brain glycogen concentration and turnover in the awake ratIn-Young Choi
Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, 2021 6th Street SE, Minneapolis, MN 55455, USA
Neurochem Int 43:317-22. 2003..Absolute quantification of the total concentration of brain glycogen in the awake, normoglycemic rat yielded 3.3+/-0.8 micromol/g (n=6, mean+/-S.D.)... - Neurochemical changes in Huntington R6/2 mouse striatum detected by in vivo 1H NMR spectroscopyIvan Tkac
Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota 55455, USA
J Neurochem 100:1397-406. 2007..Longitudinal monitoring of changes in these metabolites may provide quantifiable measures of disease progression and treatment effects in both mouse models of HD and patients... - 1H-localized broadband 13C NMR spectroscopy of the rat brain in vivo at 9.4 TPierre-Gilles Henry
Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota Medical School, Minneapolis Minnesota
Magn Reson Med 50:684-92. 2003..This unprecedented amount of information will be useful for metabolic modeling studies aimed at understanding brain energy metabolism and neurotransmission in the rodent brain... - Evaluation of brain mitochondrial glutamate and alpha-ketoglutarate transport under physiologic conditionsDeborah A Berkich
Department of Cellular and Molecular Physiology, Pennsylvania State University, College of Medicine, 500 University Drive, Hershey, PA 17033, USA
J Neurosci Res 79:106-13. 2005..The alpha-ketoglutarate pool is far smaller than the glutamate pool and will therefore approach steady state faster than will glutamate at the metabolite transport rates measured... - Comparison of three commercially available radio frequency coils for human brain imaging at 3 TeslaRalf Mekle
Centre d Imagerie BioMedicale, Ecole Polytechnique Federale de Lausanne, EPFL SB IPMC LIFMET, CH F0 572 Batiment CH, Station 6, 1015 Lausanne, Switzerland
MAGMA 21:53-61. 2008.... - Mathematical modeling of (13)C label incorporation of the TCA cycle: the concept of composite precursor functionKai Uffmann
Laboratory of Functional and Metabolic Imaging, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
J Neurosci Res 85:3304-17. 2007..This approach allows one to determine metabolic rates by fitting explicit mathematical functions to measured time courses... - Proton T2 relaxation time of J-coupled cerebral metabolites in rat brain at 9.4 TLijing Xin
Laboratory of Functional and Metabolic Imaging, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
NMR Biomed 21:396-401. 2008..The T2 values of J-coupled metabolites ranged from 89 +/- 8 ms (glutamate) to 148 +/- 14 ms (myo-inositol)... - Localized short-echo-time proton MR spectroscopy with full signal-intensity acquisitionVladimir Mlynarik
Laboratory of Functional and Metabolic Imaging, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
Magn Reson Med 56:965-70. 2006.... - Dynamic or inert metabolism? Turnover of N-acetyl aspartate and glutathione from D-[1-13C]glucose in the rat brain in vivoIn Young Choi
The Nathan Kline Institute, Medical Physics, Orangeburg, New York 10962, USA
J Neurochem 91:778-87. 2004..8 micromol/g, comparable to the cortical glutathione concentration. We conclude that NAA and GSH are completely turned over and that the metabolism is extremely slow (< 0.05% of the glucose metabolic rate)... - Relaxivity of Gd-based contrast agents on X nuclei with long intrinsic relaxation times in aqueous solutionsRuud B van Heeswijk
Laboratory for Functional and Metabolic Imaging, Ecole Polytechnique Federale de Lausanne, CH 1015 Lausanne, Switzerland
Magn Reson Imaging 25:821-5. 2007..1- to 10-microM contrast agents should be detectable, provided sufficient sensitivity is available, such as that afforded by hyperpolarization, recently introduced to in vivo imaging... - Quantitative proton spectroscopic imaging of the neurochemical profile in rat brain with microliter resolution at ultra-short echo timesVladimir Mlynarik
Laboratory for Functional and Metabolic Imaging, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
Magn Reson Med 59:52-8. 2008..We conclude that it is feasible to achieve a sensitivity that is sufficient for quantitative mapping of the neurochemical profile at microliter spatial resolution...