ANTINOCICEPTIVE, ANTIINFLAMMATORY AND ANTIPYRETIC EFFECTS OF LAPIDIN,A BICYCLIC SESQUITERPENE

Lapidin, a bicyclic sesquiterpene from Ferula linkii Webb, has been ev aluated for antinociceptive, anti-inflammatory, and antipyretic activi ties in mice and rats. Lapidin, vehicle, or the appropriate reference analgesic and anti-inflammatory compounds (acetylsalicylic acid [ASA] and indomethacin) were injected i.p. The more conspicuous effects of l apidin were: 1) a significant protective effect (17-62 %; 2.5-20 mg/kg ) towards writhings and stretchings induced by acetic acid in mice; 2) a significant antinociceptive effect on jumping responses in the hot- plate test (120 seconds at 15 mg/kg vs. 40 and 85 seconds in vehicle a nd ASA-treated mice, respectively); 3) a significant dose-dependent (5 -15 mg/kg) antinociceptive effect against mechanical noxious stimuli; 4) a dose-dependent anti-inflammatory effect in the carrageenan-induce d edema which, at the higher dose (20 mg/kg), was comparable (65 % inh ibition of paw swelling at 3 hours) to that obtained after indomethaci n (10 mg/kg); and 5) a moderate antipyretic effect against yeast-induc ed hyperthermia. Present results demonstrate that lapidin possesses an tinociceptive, anti-inflammatory, and less pronounced antipyretic effe cts comparable to those of classical non-steroid anti-inflammatory dru gs, which make it worthy of further investigations as an antinocicepti ve and anti-inflammatory drug.