title: X-irradiation-induced emesis in Suncus murinus.
abstract: X-irradiation-induced emesis was investigated in Suncus murinus, a house musk shrew. Whole body X-irradiation caused emesis, and the calculated ED50 value that induced emesis in 50% of animals was 429 cGy. At the irradiation dose of 800 cGy all the animals vomited 10.0 +/- 2.4 times with a latency of 20.0 +/- 2.9 min. The emetogenic effect of X-irradiation was dependent on the part of the body exposed. Abdominal X-irradiation at 1000 cGy caused emesis in all animals studied, whereas the same dose to the head had no emetogenic effect. We investigated several prophylactic methods against X-irradiation-induced emesis. Surgical vagotomy completely inhibited the emesis induced by 800 cGy X-irradiation. Emesis was also prevented by the subcutaneous administration of tropisetron (ICS 205-930, a selective serotonergic 5-HT3 receptor antagonist) with an ID50 value of 29 micrograms/kg. These results suggest that (1) suncus is a useful experimental animal for the study of radiation-induced emesis and the development of prophylactic drugs, (2) serotonin plays an important role in X-irradiation-induced emesis, and (3) X-irradiation-induced emesis is very similar to that caused by cancer chemotherapeutic agents.
authors.affiliation: Department of Chemical Pharmacology Faculty of Pharmaceutical Sciences, University of Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Torii
authors.forename: M
authors.initials: M
authors.lastname: Shikita
authors.forename: H
authors.initials: H
authors.lastname: Saito
authors.forename: N
authors.initials: N
authors.lastname: Matsuki
mesh_terms: D000818:Animals; D000932:Antiemetics / Q000627:therapeutic use; D005260:Female; D007211:Indoles / Q000627:therapeutic use; D012788:Shrews; D000077526:Tropisetron; D014628:Vagotomy; D014839:Vomiting / Q000209:etiology* / Q000517:prevention & control; D014916:Whole-Body Irradiation / Q000009:adverse effects*
chemical_list: D000932:Antiemetics; D007211:Indoles; D000077526:Tropisetron