Evaluation of the role of norepinephrine in the reinforcing effects of psychomotor stimulants in rhesus monkeys.
Rhesus monkeys were surgically prepared with intravenous catheters and allowed to self-administer cocaine (0.03-0.1 mg/kg/injection) under a fixed-ratio 10 schedule of drug delivery during daily 2-hour experimental sessions. When responding was stable for cocaine, saline or various doses of nisoxetine, a selective norepinephrine (NE) reuptake blocker, was substituted for cocaine for 5-7 consecutive sessions. Nisoxetine failed to maintain self-administration responding at any dose in 3 of 4 monkeys tested. Pre-session administration of the selective alpha 1 NE receptor blocker prazosin (0.2-1.6 mg/kg, IV, 15 minutes pre-session) did not systematically alter cocaine self-administration in any monkey. The results are in contrast to what has been found with DA agonists and antagonists and are consistent with the belief that NE does not play a primary role in the reinforcing properties of psychomotor stimulants.
D000818:Animals; D003042:Cocaine / Q000008:administration & dosage; D005260:Female; D005473:Fluoxetine / Q000008:administration & dosage / Q000031:analogs & derivatives; D008253:Macaca mulatta; D008297:Male; D009638:Norepinephrine / Q000037:antagonists & inhibitors / Q000502:physiology*; D011224:Prazosin / Q000494:pharmacology; D011597:Psychomotor Performance / Q000187:drug effects* / Q000502:physiology; D012054:Reinforcement, Psychology; D012646:Self Administration
D005473:Fluoxetine; C011386:nisoxetine; D003042:Cocaine; D009638:Norepinephrine; D011224:Prazosin