PGD2 effects on rodent behavior and EEG patterns in cats.

Prostaglandin (PG) D2 was studied to determine the pharmacological effects of this PG on the central nervous system. PGD2 (0.45-4.05 mg/kg) decreased spontaneous locomotor activity in rats by as much as 66% of control, however, the neuromuscular coordination of mice, treated at the same doses of PGD2, was not impaired. PGD2 (0.05-4.05 mg/kg) also increased pentobarbital sleeping time in mice from 42% to 238% of control, in a dose-related manner. PGD2 did not prevent convulsions induced in response to electroshock or pentylenetetrazol. Cats monitored for EEG responses to PGD2 infusion displayed variable sensitivity to different doses (16-3000 microgram) of drug, however, the characteristic response to PGD2 was the conversion from a uniform low voltage, fast wave pattern to high voltage, slow waves. Cats administered PGD2 were sedated and sometimes catatonic, and displayed brief periods of hypotension, bradycardia, diarrhea, analgesia and hyperthermia at higher doses of the drug. Thus, PGD2 possesses sedative properties in rodents and cats and may have a role in the central nervous system.