Action of ondansetron and CP-99,994 on cisplatin-induced emesis and locomotor activity in Suncus murinus (house musk shrew)

Species possessing the emetic reflex are useful for anti-emetic screening. Assessing the potential of novel drugs to simultaneously reduce nausea and emesis in animals is problematic, however. In the present studies, therefore, the behavioural repertoire of Suricus murinus in response to the emetic chemotherapeutic drug cisplatin was studied in an attempt to characterize behaviours (including spontaneous locomotor activity) that may be relevant to nausea status. Cisplatin at 30 mg/kg, intraperitoneal, induced a robust emetic response but did not induce novel behaviour and failed to affect spontaneous locomotor activity. Ondansetron at 3 mg/kg, subcutaneous, and CP-99,994 at 10 mg/kg, subcutaneous, reduced emesis by 98% and 40.7%, respectively. Both ondansetron and C13-99,994, however, were inactive in modifying spontaneous locomotor activity in either cisplatin-treated or normal animals. Results are discussed in relation to other animal models of nausea and emesis.