THE GONADOTROPIC HORMONES 



the cortical hypertrophy due to prolan in the rabbit is pre- 

 vented by thyroidectomy. 



De Fremery (1934) stated that the weight of the male 

 rat's adrenal before puberty is correlated with body-weight, 

 whereas after puberty adrenal weight does not increase as 

 rapidly as that of the rest of the body. (In adult female 

 animals, adrenal weight is proportional to body-weight.) The 

 injection of doses of prolan causing an enormous hypertrophy 

 of the seminal vesicles did not cause any fall in the weight 

 of the adrenals in immature male rats; as in normal imma- 

 ture males, there was found still to be a correlation between 

 the weight of the body and of the adrenal glands. 



3. The thymus. — Klein (1935-36) investigated the action 

 of prolan on the thymus of guinea pigs. Atrophic changes 

 were noted in both sexes. In females, however, the number 

 of Hassal's corpuscles appeared to be increased and was ac- 

 companied by the appearance of cells described by Fulci as 

 characteristic of the thymus of pregnant guinea pigs. Prolan 

 did not produce such changes in male animals. 



4. The epiphysis. — There is not acceptable evidence that 

 pineal extract antagonizes the gonadotropic action of prolan. 

 Vinals (1935) even believed that a suspension of beef pineal 

 synergizes with prolan in some of its ovarian effects (see also 

 the reports of Engel, 1936; Engel and Buno, 1936; Wade, 

 1937; and others). 



The metabolic efects of prolan. — Prolan (20 rat-units daily 

 for 7 days) does not alter the oxygen-consumption of albino 

 female rats (Danforth, Greene, and Ivy, 1937). Although 

 the administration of desiccated thyroid appeared to produce 

 less of a calorigenic effect after the injection of oestrogens, 

 this was not shown to be true after the injection of prolan. 



Osada (1935) believed that an increased deposition of 



extract, etc., but not prolan, cause a development of the zona reticularis in the 

 adult male mouse. In normal adult mice this zone is readily identified in females 

 but not in males. 



[135] 



