434 



PHYSIOLOGY OF GONADS 



hypophysectomized-castrated rats LTH had 

 no effect on ventral prostate weiglit. Gray- 

 hack, Bunce, Kearns and Scott (1955) made 

 the same observation for prostate weights 

 in young adult Sprague-Dawley rats, but 

 found that LTH augmented the effect of 

 testosterone propionate on prostate weight. 



A difference in response between Long- 

 Evans and Sprague-Dawley strains of rats 

 was observed by Lostroh and Li (1956). 

 In immature hypophysectomized-castrated 

 Long-Evans rats, LTH alone had no effect 

 on ventral prostate or seminal vesicle 

 weights, and no synergistic effect when ad- 

 ministered with a low dose of testosterone 

 propionate; in Sprague-Dawleys, however, 

 the weights of ventral prostates and coagu- 

 lating glands were increased by LTH but, 

 again, no synergism occurred with exoge- 

 nous androgen. Chase, Geschwind and Bern 

 (1957) reported that in immature hypo- 

 physectomized-castrated Sprague-Dawleys, 

 LTH did not affect weights of ventral pros- 

 tates or coagulating glands but it did in- 

 crease seminal vesicle weight. When LTH 

 was administered with testosterone propio- 

 nate, glandular tissue in the ventral prostate 

 was increased and weights of coagulating 

 glands (in some cases) and seminal vesicles 

 were significantly higher than with andro- 

 gen alone. 



In the immature hypophysectomized 

 Sprague-Dawley rats that were not cas- 

 trated, LTH alone did not affect ventral 

 prostate weight but when given simultane- 

 ously with ICSH it acted synergistically 

 (Segaloff, Steelman and Flores, 1956). These 

 results were confirmed by Lostroh, Squire 

 and Li (1958) for the Sprague-Dawley 

 strain, but in Long-Evans rats, LTH neither 

 increased prostatic weight, nor augmented 

 prostatic response to ICSH. 



Antliff, Prasad and Meyer (1960) have 

 shown that in the guinea pig, LTH had no 

 effect on seminal vesicles of castrated or hy- 

 pophysectomized males, but when it was 

 administered with subminimal doses of tes- 

 tosterone propionate, seminal vesicle weight 

 and epithelial height were increased. 



2. Growth Hormone {STH) 



Van der Laan (1953) found no effects of 

 STH on ventral prostate weights in young 

 hypophysectomized-castrated rats. Huggins, 



Parsons and Jensen ( 1955) observed only 

 slight effects on weights of ventral prostates 

 and seminal vesicles with administration of 

 STH to young hypophysectomized-cas- 

 trated Sprague-Dawley rats, but a syner- 

 gistic effect on weight was evident with 

 simultaneous treatment with STH and tes- 

 tosterone propionate. 



In hypophysectomized-castrated Long- 

 Evans rats (Lostroh and Li, 1956, 1957), 

 STH produced slight histologic changes and 

 significant weight increases in the ventral 

 jirostate; when administered with testoster- 

 one propionate, an additive effect on weight 

 was obtained. The changes in the seminal 

 vesicles were less evident. The effects on 

 Sprague-Dawley rats included weight in- 

 creases in ventral prostates and seminal 

 vesicles and a greatly enhanced weight re- 

 sponse when STH and testosterone propio- 

 nate were administered simultaneously (hy- 

 pophysectomized-castrates in this strain 

 gave a limited response to the androgen I . 

 Chase, Geschwind and Bern (19571 found 

 no consistent weight increases of ventral 

 prostates, coagulating glands or seminal 

 vesicles in young hypophysectomized-cas- 

 trated Sprague-Dawleys treated with STH 

 or STH and testosterone propionate. Simul- 

 taneous administration of STH, LTH and 

 testosterone, however, induced significant 

 increases in all accessories above the weights 

 produced by the androgen alone. 



Lostroh, Squire and Li (19581 deter- 

 mined that STH had no effect on the ventral 

 prostate response to ICSH in hypophysec- 

 tomized Long-Evans rats, but })roduced an 

 enhanced response in Sprague-Dawleys. It 

 was concluded that the Long-Evans strain is 

 jjreferable for the testing of crude ICSH ex- 

 tracts, inasmuch as neither STH, LTH, nor 

 both simultaneously, affect the response of 

 the ventral prostate to ICSH. 



With regard to the action of STH on his- 

 tologic structure of the prostate in hypopiiy- 

 sectomized-castrated rats, it should be noted 

 that the effects are slight; nuclei api)ear 

 vesicular, and the connective tissue stroma 

 is increased (Lostroh and Li, 1957). The 

 synergistic action of STH on prostate 

 growth in hypoi)hysectomized-castrated 

 rats when administered simultaneously with 

 testosterone is more striking. In a general 

 discussion of the many biologic effects of 



