The effects of phencyclidine and three analogues on motor performance in mice

A measure of motor impairment in which mice were required to climb to the top of an inverted screen was used to study the effects of phencyclidine. The time course of effects of phencyclidine after intravenous, intraperitoneal and per os administrations was compared. The intravenous route resulted in a rapid peak effect of activity and phencyclidine was most potent by this route. Peak effects of phencyclidine were seen by 30 min after intraperitoneal and per os administrations and the decline in activity was not very different with these two routes. However, greater peak effects were seen with intraperitoneal than per os administration. The effects of phencyclidine were also compared to ketamine, N-ethyl-phenylcyclohexylamine (PCE) and 1-[1-(2-thienyl)-cyclohexyl]-piperidine (TCP). The order of potency was PCE greater than phencyclidine greater than TCP greater than ketamine. PCE, phencyclidine and TCP had similar time courses of activity, whereas ketamine was shorter acting.