THE GONADOTROPIC HORMONES 



was completely precipitated by 5 volumes of alcohol, where- 

 as under similar conditions only 20 per cent of the newly de- 

 scribed substance could be recovered. Obviously, better data 

 are needed to establish their conclusion. 



Monnier (1936) found that lumbar or ventricular cerebro- 

 spinal fluid of patients with brain tumor (9 of 20) or other 

 cerebral disease (3 of 10) stimulated the gonads of male or fe- 

 male immature mice. Such effects were never produced by 

 normal cerebrospinal fluid. (Other reports are mentioned in 

 the previous volume.) 



Miscellaneous obs elevations. — Emery (1937) reported that 

 splenectomy in the rat does not alter various gonadotropic 

 effects of "minimal strength" pituitary transplants. Gordon 

 and others had reported differently but used prolan instead 

 of a true anterior pituitary hormone. 



THE PREPARATION, ASSAY, AND SPECIAL EFFECTS OF 

 GONADOTROPIC PITUITARY EXTRACTS 



The preparation and chemical nature of pituitary gonado- 

 tropic hormones. — The complex effects of pituitary gonado- 

 tropic extracts have led to equally complex interpretations of 

 the number of hormones secreted. Even the generally ac- 

 cepted belief that separate follicle-stimulating and luteinizing 

 hormones are secreted by the pars glandularis has not been 

 proved with convincing thoroughness. Therefore, once a 

 gonadotropic hormone has been isolated as a crystalline, 

 chemically pure substance, it will be possible rapidly to de- 

 cide many vexing questions of interpretation. 



What data have been published recently still indicate that 

 pituitary gonadotropic hormone(s) are proteins or substances 

 of protein-like nature. Tryptic digestion (or heat to a far less 

 extent) rapidly destroys pituitary hormones, causing ovula- 

 tion in rabbits or testis-stimulation in immature doves (Rid- 

 dle and others, 1936). On the other hand, tryptic digestion 

 under proper conditions appears to bring about destruction of 

 nearly all the luteinizing action of anterior pituitary extract 



