Primate social behavior as a method of analysis of drug action: studies with THC in monkeys.

The use of primate social behavior tests systems to characterize alteration of central nervous system (CNS) function by lesioning, telestimulation, and psychoactive drugs is discussed. Current observations of effects of acute and long-term chronic administration of delta9-tetrahydrocannabinol in group-caged rhesus monkeys are cited to demonstrate the sensitivity and specificity of primate social behavior test systems in characterization of CNS drugs. The time course of drug action proceeds from the acute intoxication stage (sedation, stimulation, decreased social interaction) through behavioral tolerance to the emergence of irritable aggressiveness (which is demonstrated in four different social contexts). The influence of social enviornmental factors and individual differences in social roles on the manifestation of drug effects are discussed. Possible mechanisms of drug action (on biogenic amines and synaptic receptors) compatible with the behavioral data are suggested.