Tolerance to cocaine's rate-increasing effects upon repeated administration.
Four squirrel monkeys responded daily under a fixed-interval 5-min or 8-min schedule of food-pellet delivery. Cocaine (0.03 to 1.7 mg/kg) and saline were injected before occasional daily sessions (acute administration). Some doses of cocaine produced substantial overall increases in response rate for 3 of the subjects; effects were less substantial for the remaining subject, who exhibited modest increases in response rate early in the session and during the middle portion of the intervals. A dose that increased response rate when administered acutely was then administered before each session (chronic administration). Chronic administration resulted in a reduction in the increases in response rate seen under acute administration for all subjects.
Schama
K F
KF
University of Florida.
Branch
M N
MN
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D003042:Cocaine / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D005260:Female; D007273:Injections, Intramuscular; D008297:Male; D012055:Reinforcement Schedule; D012453:Saimiri; D012965:Sodium Chloride / Q000494:pharmacology
D012965:Sodium Chloride; D003042:Cocaine