Accession Number : ADA194102
Title : Emetic Mechanism in Acute Radiation Sickness
Descriptive Note : Technical rept. 1 Dec 1982-30 Nov 1986
Corporate Author : DARTMOUTH MEDICAL SCHOOL HANOVER NH
Personal Author(s) : Borison, Herbert L.
Report Date : 20 AUG 1987
Pagination or Media Count : 57
Abstract : A dose-response relationship was established in normal cats for the evocation of vomiting within 24 h after whole-body exposure to 60Co radiation with doses ranging from 7.5 to 60 Gy delivered at 1.0 Gy/min. Vomiting was recorded oscillographically. Radiation-induced vomiting was elicited unabatedly at the optimal dose of 45 Gy in chronically postremectomized cats. Radioemetic susceptibility was evaluated in normal cats after each of two doses of radiation, from 7.5 to 60 Gy, given on successive days. Occurrence of radioemetic protection against the second irradiation was manifested in direct relation to the magnitude of the first exposure, and complete protection for 24 h resulted after second radiation exposure at the highest dose level. Postremectomized cats were also fully protected against the radioemetic effect of a second exposure at 45 Gy. All normal cats vomited in response to an emetic drug injection during the state of radioemetic refractoriness after the second irradiation at 45 Gy. A neural origin of emetic signal generated by first radiation exposure was examined in postrema-intact cats. Keywords: Ionizing radiation; Acute radiation sickness; Area postrema ablation; Spinal cord; Vagus nerve.
Descriptors : *EMESIS , *RADIATION SICKNESS , *RADIATION TOLERANCE , RADIATION , DOSAGE , IRRADIATION , EXPOSURE(PHYSIOLOGY) , RESPONSE(BIOLOGY) , IONIZING RADIATION , INJECTIONS(MEDICINE) , EMETICS , CATS.
Subject Categories : RADIOBIOLOGY
Distribution Statement : APPROVED FOR PUBLIC RELEASE