PCA: effects on ejaculation, thermoregulation, salivation, and irritability in rats.

The short term monoamine releaser p-chloroamphetamine (PCA) was injected intraperitoneally in male rats housed at 20 degrees C. Within 2 hr of PCA injections (2.5, 5.0, 8.0 or 10.0 mg/kg), rats showed ejaculation, decreased colonic temperature, increased salivation, and increased irritability. Ejaculation and salivation scores were considerably lower in the 2.5 mg/kg than in the higher dose groups, but otherwise were not dose dependent at the doses used. Hypothermia was of similar magnitude in all groups, but lasted longer in the higher dose groups. Irritability increased with dose size. In order to study the role of ambient temperature in PCA-induced behavioral changes, observations were made on an additional group or rats housed at the higher ambient temperature of 25 degrees C. In these rats an increase, rather than a decrease, in mean colonic temperature was observed following PCA injection (5 mg/kg). Ejaculation and irritability scores were similar to those observed at the lower ambient temperature, but salivation was enhanced. It is suggested that PCA induces ejaculation, salivation, irritability and, depending on the ambient temperature, either hypothermia or hyperthermia.