THE PITUITARY BODY 



ine weight in the immature rat, although suitable for the 

 biological estimation of pituitary follicle-stimulating hor- 

 mone, cannot be used for the accurate assay of prolan or the 

 active principle of pregnant-mare serum. 



The chemistry of prolan. — Prolan has not been prepared as 

 a pure substance. There is not good additional evidence that 

 it is composed of more than one gonadotropic principle, al- 

 though Brindeau, Hinglais, and Hinglais (1936) contend that 

 it is a mixture of 3 principles. Reports of the hormone's prep- 

 aration by modifications of the tannic acid, tungstic acid, or 

 benzoic acid methods as applied to urine have been made 

 by Hellbaum, Fevold, and Hisaw (1935), Freud and Hechter 

 (1936), and Ito, Hajazu, and Ueno (1936). xAlso, Fevold and 



TABLE 3 



Hisaw (1936) described a method based on the extraction of 

 the hormone from urine by means of 10 per cent cresol. The 

 effect of hydrogen-ion concentration,^' various organic re- 

 agents, etc., on the hormone has been studied by Bischoff 

 and Long (1936). 



GONADOTROPIC HORMONES ASSOCIATED WITH 

 NEOPLASMS IN MAN 



The neoplasms with which the excretion of large quantities 

 of what is probably prolan are most definitely associated 

 are hydatidiform mole and chorionepithelioma. Malignant 

 testicular neoplasms likewise may produce large quantities 

 of prolan-like hormone which, however, may differ from pro- 



^' See also Elden and Fellows (1935). 



[142] 



