Discriminative stimulus effects of the cannabinoid antagonist, SR 141716A, in delta -sup-9-tetrahydrocannabinol-treated rhesus monkeys.

This study examined whether the cannabinoid antagonist, SR 141716A, could be established as a discriminative stimulus in rhesus monkeys treated with delta -sup-9-tetrahydrocannabinol (delta -sup-9-THC). Stimulus control was established with SR 141716A (1.0 mg/kg) in 3 delta -sup-9-THC-treated monkeys (1.12 mg/kg/day) in 113-124 sessions. The SR 141716A discriminative stimulus was dose related, attenuated by an acute injection of delta -sup-9-THC, and not mimicked by cocaine or ketamine. SR 141716A-appropriate responding occasioned by temporary discontinuation of delta -sup-9-THC treatment was attenuated by delta -sup-9-THC and not ketamine. The SR 141716A discriminative stimulus in delta -sup-9-THC-treated monkeys appears to be mediated by cannabinoid receptors and could be related to delta -sup-9-THC withdrawal.