THE SOURCE OF EXCESS CREATINE FOLLOWING METHYL TESTOSTERONE1

Abstract

SINCE among the steroids only the 17-methylated compounds cause increased formation of creatine, the present studies were designed to give some information regarding the site of this action. Wilkins and Fleishmann (11) in 1941 first described the production of creatinuria in undeveloped dwarfs who were treated with methyl testosterone. Like testosterone, this compound caused increased nitrogen storage and growth, but whereas testosterone administration led to a small decrease in creatine output, methyl testosterone caused a marked increase in creatine excretion after a latent period of six to sixteen days. Samuels, Henschel and Keys (8) in 1942 described this increased creatinuria after administration of methyl testosterone to normal young men. The output rose to as high as one gram per day in certain individuals. Not only was there a creatinuria but the blood creatine levels increased. These workers, therefore, came to the conclusion that the creatinuria was due to an increased formation of creatine rather than any change in the renal threshold.