title: Lorcaserin Reduces the Discriminative Stimulus and Reinforcing Effects of Cocaine in Rhesus Monkeys.
abstract: Cocaine abuse and obesity are serious public health problems, and studies suggest that both dopamine and serotonin systems are involved in regulating the consumption of drugs and food. Lorcaserin has serotonin (5-HT)2C receptor agonist actions, is approved by the U.S. Food and Drug Administration for treating obesity, and might be effective for treating cocaine abuse. These studies characterized the pharmacokinetic and behavioral profiles of lorcaserin (intragastric administration) and determined the effectiveness of lorcaserin to alter discriminative stimulus and reinforcing effects of cocaine (intravenous administration) in rhesus monkeys. Administered acutely, lorcaserin dose-dependently increased the occurrence of yawning while decreasing spontaneous activity and operant responding for food. These effects appeared within 30-60 minutes of administration and began to dissipate by 240 minutes, a time course closely matching plasma concentrations of lorcaserin. In monkeys discriminating cocaine from saline, lorcaserin alone did not occasion cocaine-appropriate responding but shifted the cocaine dose-response curve to the right and down in two of three monkeys. When administered acutely, lorcaserin dose-dependently decreased the rate at which monkeys responded for infusions of cocaine. When administered chronically, 3.2 mg/kg lorcaserin reduced the rate of cocaine-maintained responding by 50% for the duration of a 14-day treatment period. Together, these results show that lorcaserin attenuates the discriminative stimulus effects of cocaine after acute administration and the reinforcing effects of cocaine after acute and repeated administration, consistent with the view that it might have utility in treating cocaine abuse.
authors.affiliation: Departments of Pharmacology (G.T.C., L.R.G., M.A.J., C.P.F.) and Psychiatry (M.A.J., C.P.F.), University of Texas Health Science Center, San Antonio, Texas; and South Texas Veterans Health Care System, San Antonio, Texas (G.T.C.).
authors.forename: Gregory T
authors.initials: GT
authors.lastname: Collins
authors.affiliation: Departments of Pharmacology (G.T.C., L.R.G., M.A.J., C.P.F.) and Psychiatry (M.A.J., C.P.F.), University of Texas Health Science Center, San Antonio, Texas; and South Texas Veterans Health Care System, San Antonio, Texas (G.T.C.).
authors.forename: Lisa R
authors.initials: LR
authors.lastname: Gerak
authors.affiliation: Departments of Pharmacology (G.T.C., L.R.G., M.A.J., C.P.F.) and Psychiatry (M.A.J., C.P.F.), University of Texas Health Science Center, San Antonio, Texas; and South Texas Veterans Health Care System, San Antonio, Texas (G.T.C.).
authors.forename: Martin A
authors.initials: MA
authors.lastname: Javors
authors.affiliation: Departments of Pharmacology (G.T.C., L.R.G., M.A.J., C.P.F.) and Psychiatry (M.A.J., C.P.F.), University of Texas Health Science Center, San Antonio, Texas; and South Texas Veterans Health Care System, San Antonio, Texas (G.T.C.) france@uthscsa.edu.
authors.forename: Charles P
authors.initials: CP
authors.lastname: France
mesh_terms: D061605:Administration, Intravenous; D000818:Animals; D019440:Anti-Obesity Agents / Q000493:pharmacokinetics / Q000494:pharmacology*; D001522:Behavior, Animal / Q000187:drug effects; D001552:Benzazepines / Q000493:pharmacokinetics / Q000494:pharmacology*; D003042:Cocaine / Q000037:antagonists & inhibitors* / Q000493:pharmacokinetics / Q000494:pharmacology*; D019970:Cocaine-Related Disorders / Q000188:drug therapy; D003216:Conditioning, Operant / Q000187:drug effects; D004192:Discrimination, Psychological / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005502:Food; D007441:Intubation, Gastrointestinal; D008253:Macaca mulatta; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D044405:Receptor, Serotonin, 5-HT2C / Q000187:drug effects*; D012054:Reinforcement, Psychology; D012646:Self Administration; D017366:Serotonin Receptor Agonists / Q000493:pharmacokinetics / Q000494:pharmacology*; D015000:Yawning / Q000187:drug effects
chemical_list: D019440:Anti-Obesity Agents; D001552:Benzazepines; D044405:Receptor, Serotonin, 5-HT2C; D017366:Serotonin Receptor Agonists; C506658:lorcaserin; D003042:Cocaine