THE EFFECTS OF HYPOPHYSECTOMY 



including those continuing to develop from the reduced num- 

 ber of primordial foUicles, and (2) an abnormal persistence of 

 corpora lutea (9.5-14.5 months compared with 2.5 months in 

 the normal animal) probably present at the time of hypophy- 

 sectomy. According to Swezy (1933), the rate of ovogenesis is 

 increased after hypophysectomy. Selye (1933) reported that 

 in rats hypophysectomized at an age of 18 days and killed 

 10-25 days later the ovaries contained both normal follicles 



Fig. 17. — The seminal vesicles of the rats shown in Figure ii. Left, of the 

 hypophysectomized rat; weight, 16.8 mg. Right, of the normal rat; weight,652.o mg. 



and atretic follicles; the theca-cells about the latter appeared 

 to be undergoing degeneration ("theca-deficiency cells"). 

 Selye, Collip, and Thomson (1933) described the appearance 

 of the ovaries of rats 6-8 months after hypophysectomy, 

 which was performed after the animals had become sexually 

 mature. Much of the ovary seemed to be made up of cells of 

 theca origin, the nuclear changes in which led them to de- 

 scribe the cells as "wheel-cells." Unilateral ovariectomy in 

 the hypophysectomized rat is followed not by compensatory 



[51] 



