THE PITUITARY BODY 



per g. fresh tissue) but that the concentration was higher in 

 the pars intermedia (2.01 mg. per g, fresh tissue). The pars 

 neurahs contained about one-third the concentration found 

 in the pars glandularis. That the substance with reducing 

 properties is in any way associated with the growth-promot- 

 ing hormone is doubtful (Salter, Green, and Putnam, 1934). 



The growth-promoting hormone and the glands of internal 

 secretion, i. The pituitary body. — Evans and Simpson (1928) 

 found that the gonadotropic effects of extracts of the pars 

 glandularis were prevented by the injection of a growth- 

 promoting extract; they concluded that the gonadotropic ef- 

 fects were antagonized by the growth-promoting hormone. 

 Lipschiitz and Kallas (1929) came to a similar conclusion. 

 All the authors pointed out that sexual activity is diminished 

 during the period of rapid growth. Targow (1933) castrated 

 young rats at weaning and then injected growth-promoting 

 hormone to a part of the group for about 40 days. Although 

 both the pars glandularis and the pars neuralis (posterior) 

 were smaller in the injected rats, yet the gonadotropic poten- 

 cy of the pituitary was as great as in uninjected littermate 

 rats which had also been castrated. There is no direct evi- 

 dence that the growth-promoting effects of anterior pituitary 

 extract are antagonized by the injection of gonadotropic ex- 

 tracts of the pars glandularis. Evans and others (1933) found 

 this also to be true of prolan and pregnant mare's serum. 



According to Rubinstein (1934), who administered a 

 growth-promoting extract to adult rats for more than 5 

 months, the weight-response was relatively greater in the fe- 

 male rats. The weight of the pituitary body of the female 

 rats was not changed; but, as in normal rats, it was greater 

 than that of the injected male rats. In the injected male rats, 

 however, the pituitary body was significantly heavier in 

 comparison with that of normal males. 



Evans, Meyer, and Simpson (1932) concluded that "sex- 

 free" growth-promoting hormone markedly potentiated the 



[96] 



