GONADOTROPIC SUBSTANCES 



after hypophysectomy. The important direct and indirect 

 results of prolan injection were hypertrophy of the theca cells 

 and interstitial cells and persistent oestrus (see Fig. 38). 

 Oestrus did not necessarily occur if a long period elapsed be- 

 tween hypophysectomy and prolan treatment. Anterior-lobe 

 implants caused ovarian hypertrophy due to follicular 

 growth (the follicles might be cystic and contain blood) and 

 corpus luteum formation. The corpora lutea were larger 

 than those formed after luteinization of the theca due to 

 prolan. ^Apparently Noguchi (1932) was the first to describe 

 theca luteinization as a result of prolan administration to 

 hypophysectomized rats. Selye, Collip, and Thomson (1933) 

 confirmed and extended the observation of Noguchi. 



Collip, Selye, and Thomson (1933) believed that prolan, 

 as in the normal immature male rat, stimulated Leydig's cells 

 but had no effect on spermatogenesis in hypophysectomized 

 rats after degeneration of the tubules had appeared. Smith 

 and Leonard (1934), however, were able to maintain sperma- 

 togenesis (including fertility) by prolan administration to 

 adult rats soon after hypophysectomy (see Fig. 39). Despite 

 continued administration, regression of the effects on both 

 spermatogenesis and Leydig's cells took place. The impor- 

 tant effect in immature hypophysectomized male rats was a 

 stimulation of the interstitial cells. Particularly in immature 

 rats did implants restore the testes to a more nearly normal 

 condition (e.g., spermatogenesis)." 



The production of ovulation in hypophysectomized rabbits 

 has already been discussed (pp. 194-95). McPhail (1933) 

 compared the effects of anterior pituitary extract and prolan 

 in hypophysectomized female ferrets; in these animals pro- 

 lan produced some follicular growth (and atresia) whereas 

 anterior-lobe extract caused chiefly a theca luteinization. 



" For other reports on the effect of prolan in hypophysectomized male and fe- 

 male rats see: Reichert and others, Wallen-Lawrence and van Dyke (1931); 

 Freud, Kraul (1932); Freud, Wade, Wade and others (1933). 



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