DOSE-SURVIVAL TIME RESPONSE OF SUNCUS MURINUS FROM WHOLE-BODY IRRADIATION

Suncus munnus/Dose-survival time response/Weight loss The overall survival time response of Suncus murinus9 one of the insectivora, under wholebody x-irradiation in the dose range of 500 to 50,000 rad was investigated. Three segments of bone marrow, gastrointestinal (GI), and central nervous system (CNS) deaths in the dosesurvival time response curve were similar to those of other species such as mice, rats, and mongolian gerbils. The mean survival time with the bone marrow syndrome was about 9 days after 700 and 800 rads. The LD/50 was 736 ± 30 rad in comparison with 547 ± 15 rad in C3H/He mice. Typical severe GI death manifested within 5.5-4.6 days following doses between 1,200 and 10,000 rad, where the survival time was almost constant. In spite of the absence of large intestinal type mucosa in this species, the relationship between transit time of the epithelial cells along villus wall (about 50 hrs) and the survival time with the typical GI syndrome was similar to those of data obtained with various rodents possessing a large intestine. CNS death was evident above 20,000 rad, and the survival time rapidly decreased with dose increase. A pattern of dose-weight loss response was found to correspond directly with the dose required to initiate the syndrome involved, as the curve can be mostly superimposed on the dose-survival time response curve if the weight loss is inversed. © 1984 Oxford University Press. All rights reserved.