Effect of Testicular Hormone on Hypophysectomized Rats

Abstract

The purpose of these experiments was to analyze further the factors necessary for the maintenance of the prostate. It is well known that prostatic atrophy follows either hypophysectomy or castration. The atrophy which follows castration can be prevented by the use of testicular hormone. Moore and Price 1 believe that the prostatic atrophy which follows hypophysectomy is entirely secondary to the changes which occur in the testes. Moore has quoted unpublished experiments by Vatna that testicular extracts maintain the prostate in hypophysectomized rats. Moore believes that secretions produced by the hypophysis stimulate the functions of the gonads, that is, both germ cell production, and hormone secretion, and that the prehypophyseal hormone has no direct action on the prostate. It is not impossible, however, that under normal physiologic conditions, the prostate is supported directly by both the hypophyseal and testicular hormones. Some experimental evidence supports this latter theory. 2

We have injected hypophysectomized rats with a hormone prepared from urine which is believed to be derived from the testes. 3 The dose was calculated to be that which would scarcely replace the normal secretion from the testes. If the hypophyseal hormone exerts a direct influence on the prostate it would be expected that, under these conditions, atrophy of the prostate would ensue. The table shows some typical findings in 3 rats that were littermates. These findings are in complete accord with Moore's theory of prostatic maintenance. The histologic appearance of the organs of these animals was even more striking than the gross appearance or weight. There seems to he no question that the prostate can be maintained by the thermostable hormone in urine in the complete absence of the liypophysis or hypophyseal secretions. In addition to the above findings in the prostate a singularly interesting observation has been made in regard to the testes.