THE PITUITARY BODY 



mone has been detected in the pituitary of the fetuses of man, 

 the ox, and the pig. For detecting gonadotropic hormone in 

 the pituitary of the human fetus, the immature mouse usually 

 has been employed. The hormone (or hormones) is said to be 

 present after the fifth lunar month of gestation but not before 

 (Siegmund and Mahnert, 1928; Schultze-Rhonhof and Nie- 

 denthal 1929; Philipp, 1930; and Wirz, 1933). Schultze-Rhon- 

 hof and Niedenthal stated that the pituitary of the ox fetus 

 contains the hormone. In the pig fetus, growth-promoting hor- 

 mone is detected first (crown-rump length: 9-1 1 cm.); later, 

 just before testicular growth becomes rapid (crown-rump 

 length: 17-18 cm.), gonadotropic hormone can be detected 

 (Smith and Dortzbach, 1929). ^According to Catchpole and 

 Lyons (1934) the pituitary of horse fetuses (crown-rump 

 length: 50-90 cm.) only infrequently contains gonadotropic 

 hormone(s). 



Corey (1928) was unsuccessful in his attempts to alter the 

 gonads of rats (after the fifteenth day of prenatal life) by in- 

 jecting a suspension of the rat pituitary into the peritoneal 

 cavity of the fetuses.'''' However, Aron (1933) stated that the 

 injection of an anterior-lobe extract into guinea pig fetuses 

 longer than 40 mm. caused a development of interstitial cells 

 in the testis (sometimes with secondary effects on the epidi- 

 dymides and seminal vesicles in fetuses longer than 80 mm.); 

 in the female fetus, he observed a hypertrophy of the inter- 

 stitial cells in the medulla and at the hilum of the ovary. 



According to Swezy (1933-34) the pituitary of the rat 1-13 

 days old has no gonadotropic effect on the testes and sec- 

 ondary organs of the hypophysectomized rat but does have 

 such an effect on the sexual organs of normal immature male 

 rats. She therefore postulated that the implantation of the 

 pituitary of very young rats stimulates the secretion of 

 gonadotropic hormone by the pituitary of the normal imma- 



I'The equivalent of only 2-5 per cent of a whole pituitary was injected on alter- 

 nate days. 



[158] 



