THE PITUITARY BODY 



Gomez, Turner, Gardner, and Hill (1937) observed no de- 

 velopment of the rudimentary mammary glands in com- 

 pletely hypophysectomized male mice receiving injections of 

 various oestrogens (50-500 international units weekly). If, 

 however, a very minute fragment of the pars glandularis re- 

 mained, the injection of oestrogen brought about mammary 

 growth and development. Likewise in male or female rats 

 oestradiol benzoate will cause no growth of the breasts after 

 hypophysectomy, although this action is not prevented by 

 gonadectomy (Reece, Turner, and Hill, 1936). Atrophy of 

 the mammary glands due to the removal of the pituitary 

 from the rat cannot be halted by oestrone; however, inani- 

 tion seems to be an important factor (Astwood, Geschickter, 

 and Rausch, 1937). Other experiments by Gomez and Tur- 

 ner (1936), who used guinea pigs, also lead to the conclusion 

 that growth and development of the mammary ducts and 

 parenchyma following the injection of moderate to enormous 

 doses of oestrone or oestradiol benzoate (e.g., 25-1,000 inter- 

 national units daily) cannot take place after hypophysectomy 

 has been performed.' If, however, hypophysectomized male 

 guinea pigs receive implants of the pituitary of male rats in 

 which breast development has been induced by injections of 

 oestrone, growth of the nipples and breasts including the de- 

 velopment of alveoli occurs, whereas implants from rats to 

 which no oestrone has been given do not affect the recipient 

 guinea pig's rudimentary nipples and breasts (Gomez, Tur- 

 ner, and Reece, 1937). x^ccording to Robson (1936), little or 

 no development of the mammary glands occurs in rabbits 

 hypophysectomized about the 22-24 ^iay of pregnancy de- 



Seidenstein (1935) found that oestrone in combination with progestin caused about 

 equally good development of the mammary glands in spayed rabbits with an intact 

 pituitary or after partial or complete hypophysectomy. Do these findings indicate 

 that the animals used were not completely hypophysectomized? According to 

 Gomez and others (1937), remnants of the anterior pituitary, too small to main- 

 tain the gonads or the adrenals, permit the response of the mammary gland of the 

 mouse to an oestrogen. 



' The growth of the nipple due to administered oestrogen is not affected by 

 hypophysectomy (Gomez and Turner, 1936). 



[154] 



