Leonard L Howell

Summary

Affiliation: Emory University
Country: USA

Publications

  1. pmc Interactions between the mGluR2/3 agonist, LY379268, and cocaine on in vivo neurochemistry and behavior in squirrel monkeys
    Rayna M Bauzo
    Division of Neuroscience, Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd, NE, Atlanta, GA 30329, USA
    Pharmacol Biochem Behav 94:204-10. 2009
  2. ncbi request reprint Comparative behavioral pharmacology of cocaine and the selective dopamine uptake inhibitor RTI-113 in the squirrel monkey
    L L Howell
    Yerkes Regional Primate Research Center, Emory University, Atlanta, Georgia, USA
    J Pharmacol Exp Ther 292:521-9. 2000
  3. ncbi request reprint Olanzapine-induced suppression of cocaine self-administration in rhesus monkeys
    Leonard L Howell
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    Neuropsychopharmacology 31:585-93. 2006
  4. pmc Nonhuman primate neuroimaging and the neurobiology of psychostimulant addiction
    Leonard L Howell
    Department of Psychiatry and Behavioral Sciences, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    Ann N Y Acad Sci 1141:176-94. 2008
  5. ncbi request reprint Functional imaging and neurochemical correlates of stimulant self-administration in primates
    Leonard L Howell
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    Psychopharmacology (Berl) 163:352-61. 2002
  6. ncbi request reprint Cocaine-induced brain activation determined by positron emission tomography neuroimaging in conscious rhesus monkeys
    Leonard L Howell
    Yerkes Regional Primate Research Center, Emory University, Atlanta, GA 30322, USA
    Psychopharmacology (Berl) 159:154-60. 2002
  7. ncbi request reprint Effects of combined dopamine and serotonin transporter inhibitors on cocaine self-administration in rhesus monkeys
    Leonard L Howell
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    J Pharmacol Exp Ther 320:757-65. 2007
  8. ncbi request reprint The dopamine transporter and cocaine medication development: drug self-administration in nonhuman primates
    L L Howell
    Yerkes Regional Primate Research Center, Emory University, Atlanta, Georgia 30322, USA
    J Pharmacol Exp Ther 298:1-6. 2001
  9. ncbi request reprint Fetal development in rhesus monkeys exposed prenatally to cocaine
    L L Howell
    Yerkes Regional Primate Research Center, Emory University, Atlanta, GA 30322, USA
    Neurotoxicol Teratol 23:133-40. 2001
  10. ncbi request reprint An apparatus and behavioral training protocol to conduct positron emission tomography (PET) neuroimaging in conscious rhesus monkeys
    L L Howell
    Yerkes Regional Primate Research Center, Emory University, Atlanta, GA 30322, USA
    J Neurosci Methods 106:161-9. 2001

Research Grants

Collaborators

Detail Information

Publications45

  1. pmc Interactions between the mGluR2/3 agonist, LY379268, and cocaine on in vivo neurochemistry and behavior in squirrel monkeys
    Rayna M Bauzo
    Division of Neuroscience, Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd, NE, Atlanta, GA 30329, USA
    Pharmacol Biochem Behav 94:204-10. 2009
    ..Moreover, reinstatement of previously extinguished cocaine self-administration was not significantly attenuated by LY379268. Hence, drug interactions on neurochemistry did not correlate well with behavioral measures...
  2. ncbi request reprint Comparative behavioral pharmacology of cocaine and the selective dopamine uptake inhibitor RTI-113 in the squirrel monkey
    L L Howell
    Yerkes Regional Primate Research Center, Emory University, Atlanta, Georgia, USA
    J Pharmacol Exp Ther 292:521-9. 2000
    ..RTI-113 effectively decreased cocaine self-administration behavior, although its direct rate-altering effects may have contributed to the interactions obtained...
  3. ncbi request reprint Olanzapine-induced suppression of cocaine self-administration in rhesus monkeys
    Leonard L Howell
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    Neuropsychopharmacology 31:585-93. 2006
    ..The results indicate that olanzapine can effectively suppress cocaine self-administration behavior in nonhuman primates at doses that enhance dopamine release but do not maintain drug self-administration...
  4. pmc Nonhuman primate neuroimaging and the neurobiology of psychostimulant addiction
    Leonard L Howell
    Department of Psychiatry and Behavioral Sciences, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    Ann N Y Acad Sci 1141:176-94. 2008
    ....
  5. ncbi request reprint Functional imaging and neurochemical correlates of stimulant self-administration in primates
    Leonard L Howell
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    Psychopharmacology (Berl) 163:352-61. 2002
    ..These approaches have significant strengths and important limitations that should be considered...
  6. ncbi request reprint Cocaine-induced brain activation determined by positron emission tomography neuroimaging in conscious rhesus monkeys
    Leonard L Howell
    Yerkes Regional Primate Research Center, Emory University, Atlanta, GA 30322, USA
    Psychopharmacology (Berl) 159:154-60. 2002
    ..The acute effects of cocaine administration on cerebral blood flow may have direct relevance to the etiology of cocaine addiction...
  7. ncbi request reprint Effects of combined dopamine and serotonin transporter inhibitors on cocaine self-administration in rhesus monkeys
    Leonard L Howell
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    J Pharmacol Exp Ther 320:757-65. 2007
    ..Collectively, the results indicate that combined inhibition of DAT and SERT warrants consideration as a viable approach in the development of cocaine medications...
  8. ncbi request reprint The dopamine transporter and cocaine medication development: drug self-administration in nonhuman primates
    L L Howell
    Yerkes Regional Primate Research Center, Emory University, Atlanta, Georgia 30322, USA
    J Pharmacol Exp Ther 298:1-6. 2001
    ..Moreover, pharmacokinetic properties that result in slow onset and long duration of action may enhance their effectiveness to reduce cocaine use while limiting their abuse liability...
  9. ncbi request reprint Fetal development in rhesus monkeys exposed prenatally to cocaine
    L L Howell
    Yerkes Regional Primate Research Center, Emory University, Atlanta, GA 30322, USA
    Neurotoxicol Teratol 23:133-40. 2001
    ..Similarly, body weight, biparietal diameter, body length, and modified Apgar scores at birth did not differ significantly among experimental groups. The results indicate that surviving fetuses exhibited normal growth...
  10. ncbi request reprint An apparatus and behavioral training protocol to conduct positron emission tomography (PET) neuroimaging in conscious rhesus monkeys
    L L Howell
    Yerkes Regional Primate Research Center, Emory University, Atlanta, GA 30322, USA
    J Neurosci Methods 106:161-9. 2001
    ..Extension of the methodology to include brain activation during behavioral studies could contribute significantly to the growing discipline of behavioral neuroscience...
  11. ncbi request reprint Behavioral evaluation of hemiparkinsonian MPTP monkeys following dopamine pharmacological manipulation and adrenal co-graft transplantation
    L L Howel
    Yerkes Regional Primate Research Center and Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA 30322, USA
    Cell Transplant 9:609-22. 2000
    ..The results demonstrate recovery of behavioral function after surgical treatment, with adrenal co-grafted monkeys showing the greatest degree of improvement...
  12. pmc Neurobiological changes mediating the effects of chronic fluoxetine on cocaine use
    Eileen K Sawyer
    Neuroscience Program, Emory University, Atlanta, GA, USA
    Neuropsychopharmacology 37:1816-24. 2012
    ..Fluoxetine may not be useful for treatment of ongoing cocaine abuse but may be useful in relapse prevention...
  13. pmc Relationship between rate of drug uptake in brain and behavioral pharmacology of monoamine transporter inhibitors in rhesus monkeys
    Heather L Kimmel
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA
    Pharmacol Biochem Behav 90:453-62. 2008
    ..Collectively, these results indicate that the rate of drug entry in brain can play an important role in the behavioral pharmacology of psychomotor stimulants...
  14. ncbi request reprint Effects of dopamine transporter inhibitors on cocaine self-administration in rhesus monkeys: relationship to transporter occupancy determined by positron emission tomography neuroimaging
    Kimberly P Lindsey
    Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd NE, Atlanta, GA 30329, USA
    J Pharmacol Exp Ther 309:959-69. 2004
    ..Moreover, the behavioral profile of DAT inhibitors may be influenced by actions at other monoamine transporters...
  15. pmc Faster onset and dopamine transporter selectivity predict stimulant and reinforcing effects of cocaine analogs in squirrel monkeys
    Heather L Kimmel
    Division of Neuroscience, Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, United States
    Pharmacol Biochem Behav 86:45-54. 2007
    ..Hence, there was a general trend for compounds that had a faster onset and/or DAT selectivity to produce significant behavioral-stimulant and reinforcing effects...
  16. pmc Cortical activation during cocaine use and extinction in rhesus monkeys
    Leonard L Howell
    Yerkes National Primate Research Center, Emory University, 954 Gatewood Road NE, Atlanta, GA 30329, USA
    Psychopharmacology (Berl) 208:191-9. 2010
    ..Neuroimaging studies have begun to define neurobiological substrates underlying the acute effects of cocaine or cocaine cues in cocaine-dependent subjects...
  17. ncbi request reprint Interaction of cocaine and dopamine transporter inhibitors on behavior and neurochemistry in monkeys
    Brett C Ginsburg
    Yerkes National Primate Research Center, Emory University, 954 Gatewood Road NE, Atlanta, GA 30329, USA
    Pharmacol Biochem Behav 80:481-91. 2005
    ..Importantly, there was little evidence of additivity on behavioral or neurochemical measures when cocaine was administered in combination with behavioral-stimulant doses of the DAT inhibitors...
  18. ncbi request reprint In vivo comparison of the reinforcing and dopamine transporter effects of local anesthetics in rhesus monkeys
    Kristin M Wilcox
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA
    Synapse 58:220-8. 2005
    ..Overall, reinforcing effects were consistent with DAT effects determined with in vivo techniques. The results further support a role for the DAT in the abuse liability of local anesthetics...
  19. pmc Effects of serotonin 2C receptor agonists on the behavioral and neurochemical effects of cocaine in squirrel monkeys
    Daniel F Manvich
    Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
    J Pharmacol Exp Ther 341:424-34. 2012
    ....
  20. pmc Effects of cocaine self-administration history under limited and extended access conditions on in vivo striatal dopamine neurochemistry and acoustic startle in rhesus monkeys
    Porche Kirkland Henry
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA
    Psychopharmacology (Berl) 205:237-47. 2009
    ..The transition from infrequent and controlled cocaine use to dependence may involve enduring changes in neurobiology as a consequence of persistent drug use...
  21. ncbi request reprint Measurement of dopamine transporter occupancy for multiple injections of cocaine using a single injection of [F-18]FECNT
    John R Votaw
    Department of Radiology, Emory University, 1364 Clifton Road NE, Atlanta, GA 30322, USA
    Synapse 44:203-10. 2002
    ..Two advantages of this technique are: reduced variability in dose-response curves because the subject is his/her own control, and the (18)F label allows evaluation of longer-acting drugs...
  22. pmc Behavioral and neurochemical effects of cocaine and diphenhydramine combinations in rhesus monkeys
    Matthew L Banks
    Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd, Atlanta, GA 30329, USA
    Psychopharmacology (Berl) 205:467-74. 2009
    ..While DPH abuse is infrequent, recent preclinical evidence suggests that DPH and cocaine combinations may have enhanced reinforcing properties...
  23. pmc Impact of early life stress on the reinforcing and behavioral-stimulant effects of psychostimulants in rhesus monkeys
    Sarah B Ewing Corcoran
    Yerkes National Primate Research Center bDepartment of Psychiatry and Behavioral Sciences, Emory University, Atlanta, Georgia 30329, USA
    Behav Pharmacol 21:69-76. 2010
    ..Taken together, the results of this study do not provide support for early life stress leading to enhanced vulnerability to stimulant use in the nonhuman primate model employed...
  24. pmc Acute brain metabolic effects of cocaine in rhesus monkeys with a history of cocaine use
    Porche Kirkland Henry
    Division of Neuroscience, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
    Brain Imaging Behav 4:212-9. 2010
    ..The identification of brain regions progressively influenced by drug exposure may be highly relevant toward efforts to develop treatments for cocaine addiction...
  25. pmc Effects of histamine H(3) receptor activation on the behavioral-stimulant effects of methamphetamine and cocaine in mice and squirrel monkeys
    Matthew L Banks
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    Pharmacology 83:164-9. 2009
    ..The aim of the present study was to examine the role of H(3)R in the behavioral-stimulant effects of cocaine and METH in mice and monkeys...
  26. doi request reprint Simultaneous measurement of extracellular dopamine and dopamine transporter occupancy by cocaine analogs in squirrel monkeys
    Heather L Kimmel
    Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329, USA
    Synapse 66:501-8. 2012
    ..These studies also indicate that acute cocaine administration decreases the availability of plasma membrane DAT for binding, even after cocaine is no longer blocking DA uptake as evidence by a return to basal DA levels...
  27. pmc Cocaine-induced reinstatement during limited and extended drug access conditions in rhesus monkeys
    Porche Kirkland Henry
    Department of Psychiatry and Behavioral Sciences, Emory University, Yerkes National Primate Research Center, Atlanta, GA 30329, USA
    Psychopharmacology (Berl) 204:523-9. 2009
    ..The progression of addiction from controlled to compulsive drug use leads to serious adverse consequences, including a greater propensity to relapse to drug use after sustained periods of abstinence...
  28. pmc The serotonin 2C receptor antagonist SB 242084 exhibits abuse-related effects typical of stimulants in squirrel monkeys
    Daniel F Manvich
    Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
    J Pharmacol Exp Ther 342:761-9. 2012
    ..The observed interactions with cocaine and the substitution for cocaine self-administration may be indicative of some degree of abuse potential in humans...
  29. pmc Influence of chronic dopamine transporter inhibition by RTI-336 on motor behavior, sleep, and hormone levels in rhesus monkeys
    Monica L Andersen
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    Exp Clin Psychopharmacol 20:77-83. 2012
    ..Chronic treatment with RTI-336 has a mild but significant stimulant effect, as evidenced by the significant increase in activity during the evening period which may cause minor disruptions in sleep measures...
  30. ncbi request reprint Evaluation of carbon-11-labeled 2beta-carbomethoxy-3beta-[4'-((Z)-2-iodoethenyl)phenyl]nortropane as a potential radioligand for imaging the serotonin transporter by PET
    Christophe Plisson
    Department of Radiology, Emory University, 1364 Clifton Road, Atlanta, GA 30322, USA
    J Med Chem 49:942-6. 2006
    ..Synthesis of the labeling precursor, radiosynthesis of [(11)C]ZIENT, and in vivo evaluation in anesthetized and awake monkeys have been performed to determine the suitability of [(11)C]ZIENT as a PET agent for SERT imaging...
  31. pmc The cystine-glutamate transporter enhancer N-acetyl-L-cysteine attenuates cocaine-induced changes in striatal dopamine but not self-administration in squirrel monkeys
    Rayna M Bauzo
    Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd, NE, Atlanta, GA 30329 4208, USA
    Pharmacol Biochem Behav 101:288-96. 2012
    ..The present results in nonhuman primates do not support the use of NAC as a pharmacotherapy for cocaine abuse, although rodent and clinical studies suggest otherwise...
  32. ncbi request reprint Serotonergic attenuation of the reinforcing and neurochemical effects of cocaine in squirrel monkeys
    Paul W Czoty
    Yerkes Regional Primate Research Center, Emory University, Atlanta, Georgia 30322, USA
    J Pharmacol Exp Ther 300:831-7. 2002
    ..These findings extend those reported previously for the behavioral-stimulant effects of cocaine and identify a potential neurochemical mechanism underlying drug interactions on behavior...
  33. ncbi request reprint Changes in extracellular dopamine during cocaine self-administration in squirrel monkeys
    Heather L Kimmel
    Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30322, USA
    Synapse 56:129-34. 2005
    ..The results suggest that the environmental context associated with drug self-administration can modulate cocaine-induced elevations in extracellular dopamine...
  34. pmc Behavioral and neurochemical effects of amphetamine analogs that release monoamines in the squirrel monkey
    Heather L Kimmel
    Division of Neuroscience, Yerkes National Primate Research Center, Emory University, 954 Gatewood Road, NE, Atlanta, GA 30329, United States
    Pharmacol Biochem Behav 94:278-84. 2009
    ..In addition, these results support further investigation of PAL-313 and similar compounds as a potential medication for treating psychostimulant abuse...
  35. pmc Dopamine transporter-related effects of modafinil in rhesus monkeys
    Monica L Andersen
    Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd, Atlanta, GA 30329, USA
    Psychopharmacology (Berl) 210:439-48. 2010
    ..Modafinil is currently used as a treatment for daytime sleepiness...
  36. pmc Reinstatement of extinguished amphetamine self-administration by 3,4-methylenedioxymethamphetamine (MDMA) and its enantiomers in rhesus monkeys
    Jessica McClung
    Division of Neuroscience, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
    Psychopharmacology (Berl) 210:75-83. 2010
    ..The effectiveness of MDMA and its enantiomers to reinstate responding previously maintained by drug self-administration has not been thoroughly investigated...
  37. pmc Nonhuman primate neuroimaging and cocaine medication development
    Leonard L Howell
    Department of Psychiatry and Behavioral Sciences and the Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    Exp Clin Psychopharmacol 16:446-57. 2008
    ..The results indicate that combined inhibition of DAT and SERT may be a viable approach to treat cocaine addiction...
  38. ncbi request reprint Monoamine transporters and psychostimulant addiction
    Leonard L Howell
    Division of Neuroscience, Yerkes National Primate Research Center, Emory University, 954 Gatewood Road NE, Atlanta, GA 30329, USA
    Biochem Pharmacol 75:196-217. 2008
    ..However, additional clinical studies are required in order to identify safe and efficacious pharmacotherapies...
  39. pmc Neuroimaging and drug taking in primates
    Kevin S Murnane
    Yerkes National Primate Research Center, Emory University, 954 Gatewood Road NE, Atlanta, GA 30329, USA
    Psychopharmacology (Berl) 216:153-71. 2011
    ..Neuroimaging approaches provide a powerful translational approach that can link findings from humans and laboratory animals...
  40. pmc Chronic Interferon-α Decreases Dopamine 2 Receptor Binding and Striatal Dopamine Release in Association with Anhedonia-Like Behavior in Nonhuman Primates
    Jennifer C Felger
    1 Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA 2 The Winship Cancer Institute, Emory University, Atlanta, GA, USA
    Neuropsychopharmacology 38:2179-87. 2013
    ..Future studies examining the mechanisms of cytokine effects on DA release and potential therapeutic strategies to reverse these changes are warranted. ..
  41. pmc Serotonin 2A Receptors Differentially Contribute to Abuse-Related Effects of Cocaine and Cocaine-Induced Nigrostriatal and Mesolimbic Dopamine Overflow in Nonhuman Primates
    Kevin S Murnane
    Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, and Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, Georgia 30322, and Chemical Biology Research Branch, National Institute on Drug Abuse and National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland 20892
    J Neurosci 33:13367-74. 2013
    ..0 mg/kg, i.v.) dopamine overflow in the caudate nucleus but not in the nucleus accumbens. These data suggest that important abuse-related effects of cocaine are mediated by distinct striatal dopamine projection pathways. ..
  42. pmc Effects of methamphetamine self-administration on actigraphy-based sleep parameters in rhesus monkeys
    Monica L Andersen
    Yerkes National Primate Research Center, Emory University, 954 Gatewood Rd, Atlanta, GA 30329, USA
    Psychopharmacology (Berl) 227:101-7. 2013
    ..Although methamphetamine is a very commonly abused drug, to the best of our knowledge, no study has evaluated its effects on sleep during drug use and abstinence under well-controlled conditions in laboratory animals...
  43. pmc Contributions of neuroimaging to understanding sex differences in cocaine abuse
    Monica L Andersen
    Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
    Exp Clin Psychopharmacol 20:2-15. 2012
    ..This review highlights contributions of neuroimaging toward understanding the role of sex differences in the drug abuse field, specifically regarding cocaine, and identifies relevant questions that neuroimaging can effectively address...
  44. ncbi request reprint Synthesis and monoamine transporter binding properties of 3beta-(3',4'-disubstituted phenyl)tropane-2beta-carboxylic acid methyl esters
    F Ivy Carroll
    Chemistry and Life Sciences, Research Triangle Institute, Research Triangle Park, North Carolina 27709, USA
    J Med Chem 48:2767-71. 2005
    ..12 nM) and the 3'-bromo-4'-iodo analogue 3i (K(i) = 0.14 nM) are the most potent analogues at the DAT and 5-HTT, respectively. These compounds will be useful to further characterize the highly interesting behavioral profile of 3b...
  45. pmc Development of the dopamine transporter selective RTI-336 as a pharmacotherapy for cocaine abuse
    F Ivy Carroll
    Center for Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, NC 27709, USA
    AAPS J 8:E196-203. 2006
    ..Based on these studies, 3beta-(4-chlorophenyl)-2beta-[3-(4'-methylphenyl)isoxazol-5-yl]tropane (RTI-336) has been selected for preclinical development...

Research Grants4

  1. Neuropharmacology of Cocaine in Nonhuman Primates
    Leonard Howell; Fiscal Year: 2007
    ....
  2. PET IMAGING AND COCAINE NEUROPHARMACOLOGY IN MONKEYS
    Leonard Howell; Fiscal Year: 2007
    ..The results obtained will also evaluate the effectiveness of monoamine transporters as potential targets for cocaine medications development. ..