Differential action of anti-emetic drugs on defecation and emesis induced by prostaglandin E2 in the ferret

Abstract In the present studies we investigated the mechanism of action of prostaglandin E 2 (1 mg/kg, i.p.) to induce emesis and defecation and/or tenesmus in the ferret. The emesis was antagonized significantly ( P S ,3 S )-3-(2-methoxybenzylamino)-2-phenlypiperidine hydrochloride (CP-99,994; 10 mg/kg, i.p.), but neither compound reduced defecations and/or tenesmus, with ondansetron (0.3 mg/kg) actually producing a slight increase ( P 2 induced emesis. However, droperidol (1 and 3 mg/kg) and scopolamine (0.3 and 3 mg/kg) reduced significantly the defecatory and/or tenesmus response ( P 3 receptor and NK 1 tachykinin receptor antagonists could be useful in the clinic to prevent emesis but not defecations induced by prostaglandin E 2 .