COCAINE-INDUCED RAUSCH - OVERT BEHAVIOR AND PLASMA-CONCENTRATIONS IN RHESUS-MONKEYS

This study was designed to characterize the cocaine-induced rausch or hyperarousal syndrome in rhesus monkeys. This syndrome mimics the stag e observed in human abusers bingeing on cocaine and is considered cruc ial in the progression from recreational use to compulsive abuse. Howe ver, little research has focused on this important aspect of cocaine u se. Cocaine was administered i.v. at doses of 0.0, 0.5, 1.0 and 2.0 mg /kg. Plasma concentrations were determined by gas chromatograph mass s pectrometry (GC/MS) using deuterated internal standards d(3) cocaine a nd d(3) benzoyrecgonine (BE). Mean plasma concentrations of cocaine, w ere on samples collected I min after infusion, 46 +/- 31, 88 +/- 15 an d 275 +/- 116 mg/mu l in the 0.5, 1.0 and 2.0 mg/kg dose groups, respe ctively. There were no detectable concentrations of BE in any of the s pecimens nor was cocaine detected in the saline controls. Analysis of the behavioural data revealed that the 0.5 and 1.0 mg/kg results were intermediate between the results obtained at doses of 0.0 and 2.0 mg/k g and that the 1.0 mg/kg dose produced a higher response than the 0.5 mg/kg dose up to the 12 min. Regarding individual behavioural signs, t hose designated escape attempts, checking, feinting, restlessness, sea rching, vocalizing, chewing, crouching and wide-eyed were noted most f requently. The results showed dose-response relationships for both pla sma concentrations of cocaine and for the total number of overt behavi oural signs. The plasma concentrations were in the range reported for human cocaine abusers.