Acute and chronic phencyclidine effects on locomotor activity, stereotypy and ataxia in rats.
Behavioral rating scales, developed to measure phencyclidine (PCP)-induced stereotypy and ataxia in rats, were tested using acute dose-response and chronic paradigms with concomitant assessment of locomotor activity by automated counters. Also, effects of chronic PCP on apomorphine-induced stereotypy were assessed as a test of dopamine supersensitivity. A linear dose-response effect was found for measures of all three behaviors through moderate dose levels (2-6 mg/kg), but only ataxia ratings continued to increase, showing a linear relationship through the higher (8 and 10 mg/kg) doses. Chronic daily PCP administration showed progressive augmentation of stereotypy, tolerance to ataxia at 10 min post-injection, and a biphasic increase followed by decrease to day 1 levels in locomotor activity over 14 days. No significant change was found in apomorphine stereotypy following chronic PCP treatment. The chronic behavioral changes demonstrated in this study may provide a model of PCP-induced psychological and cognitive changes seen following chronic usage in man.
D000661:Amphetamine / Q000494:pharmacology; D000704:Analysis of Variance; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001259:Ataxia / Q000139:chemically induced*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D010622:Phencyclidine / Q000494:pharmacology*; D051381:Rats; D013239:Stereotyped Behavior / Q000187:drug effects*
D000661:Amphetamine; D010622:Phencyclidine; D001058:Apomorphine