400 



CELLS, TISSUES, AND ORGANISMS 



double in weight, but the stimulation achieved is far below that ob- 

 tained with testosterone. The androgens stimulate the epithelium of 

 the seminal vesicles, whereas estrogens produce hypertrophy of the 

 fibro-muscular components. 



Prostate. Castration in various species of animals and in men with 

 benign prostrate hypertrophy produces involution of the prostate gland 

 (Dorfman and Shipley, 1956; Huggins and Stevens, 1940). Involution- 

 ary changes in the immature rodent are partly prevented by the andro- 

 genic steroids secreted by the X-zone of the adrenal gland. The involu- 

 tion can be markedly accelerated by adrenalectomy. Involution of the 

 X-zone occurs with sexual maturity in the rodent, and castration of the 

 mature rat is followed by complete degeneration of the prostate gland. 



Administration of androgens can prevent the involution of the 

 prostate that occurs after castration and will also stimulate the atro- 



£ 



0.05 0.1 0.2 



TOTAL DOSE mg. 



05 



Figure 6. Effect of testosterone and estrone on seminal-vesicle weight of rat. 

 (Data from Saunders, 1958.) 



