title: Endogenous cannabinoids are not involved in cocaine reinforcement and development of cocaine-induced behavioural sensitization.
abstract: The endogenous cannabinoid system is a relatively novel discovered system consisting of cannabinoid CB1 receptors, which are expressed both in the periphery and in the central nervous system, peripheral cannabinoid CB2 receptors and endogenous cannabinoids, which are anandamide and 2-arachidonyl glycerol. The cannabinoid CB1 receptors have recently been implicated in rewarding aspects of not only the cannabinoid drug Delta9-tetrahydrocannabinol (Delta9-THC), but also of other drugs of abuse, including cocaine. The present study was designed to further investigate the role of CB1 receptors in reward-related effects of cocaine. Using the CB1 receptor selective antagonist SR141716A, the involvement of CB1 receptors in cocaine reinforcement was determined by intravenous cocaine self-administration. In addition, the effects of the CB1 receptor selective antagonist SR141716A upon the development of cocaine-induced behavioural sensitization were investigated. SR141716A did not affect cocaine reinforcement nor did it affect the development of behavioural sensitization to the locomotor stimulant effects of cocaine. These findings suggest that CB1 receptors are not involved in acute cocaine reinforcement nor in cocaine-induced behavioural sensitization.
authors.affiliation: Department of Pharmacology and Anatomy, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Stratenum, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands.
authors.forename: Heidi M B
authors.initials: HM
authors.lastname: Lesscher
authors.forename: Emily
authors.initials: E
authors.lastname: Hoogveld
authors.forename: J Peter H
authors.initials: JP
authors.lastname: Burbach
authors.forename: Jan M
authors.initials: JM
authors.lastname: van Ree
authors.forename: Mirjam A F M
authors.initials: MA
authors.lastname: Gerrits
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D063387:Cannabinoid Receptor Antagonists; D002186:Cannabinoids / Q000378:metabolism; D003042:Cocaine / Q000008:administration & dosage / Q000009:adverse effects*; D018765:Dopamine Uptake Inhibitors / Q000008:administration & dosage / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009068:Movement / Q000187:drug effects; D010880:Piperidines / Q000494:pharmacology; D011720:Pyrazoles / Q000494:pharmacology; D043882:Receptors, Cannabinoid / Q000502:physiology; D012054:Reinforcement, Psychology; D000077285:Rimonabant; D012646:Self Administration; D015819:Substance Abuse, Intravenous / Q000209:etiology* / Q000523:psychology
chemical_list: D063387:Cannabinoid Receptor Antagonists; D002186:Cannabinoids; D018765:Dopamine Uptake Inhibitors; D010880:Piperidines; D011720:Pyrazoles; D043882:Receptors, Cannabinoid; D003042:Cocaine; D000077285:Rimonabant