Studies of Long Acting Sex Hormones

1) For comparative experiments of the effectiveness of long acting male sex hormones. Each 100mg. of testosterone propionate, testosterone heptanoate, testosterone cyclopentylpropionate, testosterone isobutyrate and testosterone undecylate was dissolved in oil and injected into normal male rabbits subcutaneously and 17-ketosteroids and steroid alcohol in urine were determined and these results were compaced.2) The effectiveness of testosterone heptanoate, testosterone cyclopentylpropionate and testosterone undecylate are durable for 8 days or more. No sudden upward ascension was shown in determination of both excretes (17-ketosteroid and steroid alcohol). With testosterone isobutyrate and testosterone phenylpropionate, the durableness was inferior while testosterone propionate is temporary, and the excretive value takes sudden upwared tendency.3) The sum of the recovered values of 17-ketosteroid after the injection of each experimental steroids during 15 days were 4.0mg. for testosterone propionate, 4.47mg. for testosterone heptanoate, 3.3mg. for testosterone phenylpropionate, 5.17mg. for testosterone cyclopentylpropionate, 4.93mg. for testosterone undecylate, and4.4mg. for testosterone isobutyrate. In the same manner, the recovered values for steroid alcohol were 53mg. for testosterone propionate, 39mg. for testosterone heptanoate 48mg. for testosterone phyenylpropionate, 61 mg. for testosterone cyclopentylpropionate, 43mg. for testosterone undecylate, and 21mg. for testosterone isobutylate.