THE PITUITARY BODY 



coitus. Animals hypophysectomized i hours after the begin- 

 ning of coitus ovulate normally (after about 36 hours); the 

 corpora lutea subsequently formed do not grow, but appear 

 immature. There are no signs of pseudopregnancy 8 days 

 after copulation followed by hypophysectomy, in spite of 

 which ovulation and corpus-luteum formation occurred. At- 

 rophy and regressive changes appear in the gonads of both 

 male and female ferrets after hypophysectomy; such changes 

 are perhaps more marked if the operation is performed during 

 the period of anoestrus. If male or female ferrets are placed 

 in artificially lighted quarters, oestrus occurs during the 

 anoestrous period (Bissonnette); in the female, at least, this 

 effect is not observed after hypophysectomy. No differences 

 in the response of the uterus to oestriol is found if normal, 

 ovariectomized, and hypophysectomized anoestrous ferrets 

 are compared. 



Pregnancy in the ferret is interrupted by hypophysectomy. 

 If the operation is performed on the twenty-first day (the 

 normal period of gestation is 41-42 days), abortion or fetal 

 resorption occurs; if the operation is performed on the thirty- 

 fifth day, parturition takes place within 3 days. The young 

 may be delivered dead or living; in the latter event, they die 

 shortly after delivery. The secretion of milk by the mother 

 rarely appears postpartum, and never persists. Hypophysec- 

 tomy during lactation is promptly followed by a cessation of 

 the secretion of milk. The effects of hypophysectomy in preg- 

 nant and lactating ferrets therefore resemble those in other 

 mammals. 



Gemelli, who apparently was the first (1908) successfully 

 to hypophysectomize cats, recognized that the removal of the 

 pituitary did not immediately cause death but that changes 

 in growth and in the glands of internal secretion followed the 

 operation. Until recently, however, the mortahty in operated 

 animals has been high (Camus and Roussy, 1922; Ciminata, 

 1926). In the later, more successful operations, the approach 



[70] 



