title: Lack of tolerance to   9 -tetrahydrocannabinol in chimpanzees.
abstract: Five chimpanzees were given Delta(9)-tetrahydrocannabinol (Delta(9)THC): 1.0 milligram per kilogram of body weight for 21 days and 4.0 milligrams per kilogram of body weight for 42 days. Although accuracy and speed of performance on a delayed matching-to-sample task were significantly affected by both doses, tolerance to Delta(9)THC did not develop. No long-term behavioral effects of Delta(9)THC were observed after termination of the drug regimens.
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D002188:Cannabis / Q000494:pharmacology*; D004193:Discrimination Learning / Q000187:drug effects; D013759:Dronabinol / Q000008:administration & dosage / Q000494:pharmacology; D004361:Drug Tolerance; D005260:Female; D008297:Male; D008570:Memory, Short-Term / Q000187:drug effects; D002679:Pan troglodytes; D011930:Reaction Time / Q000187:drug effects
chemical_list: D013759:Dronabinol