Effects of Rat Strain, Stilbestrol and Testosterone on the Occurrence of Hemorrhagic Diathesis in Rats Fed a Ration Containing Irradiated Beef

Abstract

Experiments were designed to investigate the difference between 2 strains of rats (Holtzman and Sprague-Dawley), and the effects of stilbestrol and testosterone on the ocurrence of hemorrhagic diathesis. The rats were fed ground beef exposed to 5.58 Mrad doses of Co/sup 60/ gamma radiation. Mortality was 58% for Sprague-Dawley rats, significantly higher than the 22% found for Holtzman rats. The average prothrombin rate, 50 for Sprague-Dawley rats at the end of the third week was significantly lower than 83 for Holtzman rats, prothrombin rates being expressed as 1000/sec. Sprague-Dawley rats were significantly less resistant to hemorrhigic disease than Holtzmann rats. Stilbestrol completely prevented hemorrhages and subsequent deaths, but testosterone increased both. The effect of testosterone was independent of growth. Stilbestrol decreased the prothrombin rates slightly and testosterone decreased them significantly. Stilbestrol decreased body weight gains, its effect being greater on Holtzman than on Sprague-Dawley rats. Testosterone increased growth in orchiectomized rats but had no effect on feed intake. Stilbestrol decreased the weight of seminal vesicles, prostates, and tests. Testosterone increased the weight of seminal vesicles and prostates but decreased the weight of testes. Stilbestrol was more potent than testosterone in inhibiting the secretion of hormones by the pituitary. Estrogen administrationmore » did not affect the prothrombin rate of rats fed a ration containing 2.79-Mrad irradiated beef, but increased it in those that received the 5.58-Mrad irradiated beef. It is suggested that estrogen overcame defective coagulation, but had no effect when the prothrombin rate was normal. (TCO)« less