The effects of phencyclidine on amphetamine stereotypy in rats.

In two separate experiments a 9 point rating scale was used to assess the effects of various doses of phencyclidine on the behavioral stereotypy produced by d-amphetamine in rats. A dose of phencyclidine (2.5 mg/kg) which had no effect when given alone, enhanced the behavioral effects of 1 and 3 mg/kg of d-amphetamine. Higher dises (5 and 10 mg/kg) of phencyclidine produced some stereotypy when given alone but they also produced ataxia which confounded the rating of their other behavioral effects. These higher doses did not enhance the effects of d-amphetamine. This study provides further evidence that phencyclidine may have dopaminergic activity similar to amphetamine.