Effects of Cortisone on Thiamine-Deficient Young Rats. ∗

Abstract

Summary

(1) A total of 128 young male albino rats were used in 2 experiments to determine the effects of large doses of cortisone on thiamine requirements. They were fed a semi-synthetic ration from which thiamine was omitted for preliminary periods of either 10 or 18 days, followed by injections of 1 mg of cortisone daily with or without several levels of thiamine for another 18 or 12 days. (2) Pre-existent deficiency symptoms were aggravated by cortisone, resulting in decreased body growth and survival rate, priapism, cannibalism and loss of muscular coordination. The rats which were initially deficient in thiamine for the longer period, showed the most severe reactions to cortisone administration. Cortisone decreased the efficiency of converting food into body weight gains in all cases. (3) When 1 mg of thiamine per kilo of ration was fed, representing normal requirements for growing rats, there was little or no increase in body weight although most deficiency symptoms disappeared. When 5, 10 or 20 mg of thiamine per kilo of ration were fed, each level was equally effective in counteracting growth inhibition by cortisone.