THE PITUITARY BODY 



the spaying or castration of fowls, guinea pigs, rabbits, buffa- 

 loes, and oxen. In the fowl and buffalo, the pituitary weight 

 was practically doubled. All subsequent work also seems to 

 show that gonadectomy in mammals is usually followed by a 

 hypertrophy of the pituitary due to a growth of the pars 

 glandularis. 



Many authors have reported on the changes in the pitui- 

 tary of rats after castration or spaying. Among the earlier 

 reports may be mentioned those of Hatai (1913) and Addison 

 (1917). Hatai observed a hypertrophy after castration, but 

 was not convinced that a similar change occurred after spay- 

 ing. Addison studied the microscopic appearance of the gland 

 in normal and castrated rats. The most important histologic 

 change in the pituitary was in the appearance and number of 

 the basophils. Besides appearing to increase in number, these 

 cells hypertrophied and, about two months after operation, 

 became vacuolated. Subsequently the size of the vacuoles 

 as well as the number of vacuolated basophils increased. 

 These constitute the "castration-cells." Addison believed 

 that some basophils were formed from reserve cells and that, 

 months after castration, there was some reduction in the 

 number of oxyphils in part due to dedifferentiation into re- 

 serve cells. 



Stein (1933) reported that the hypertrophy of the pituitary 

 following castration in the rat was entirely due to the in- 

 creased size of the pars glandularis, which was found to be 

 increased 6^ per cent (castrated, 10.52 mg.; normal, 6.59 

 mg.). The relative weight of the pars glandularis after cas- 

 tration was 87.2 per cent in comparison with 82.3 per cent in 

 normal rats. Stein emphasized that colloid, practically ab- 

 sent in the pituitary of the normal rat, could be found in 

 great abundance after castration. 



The castration-cell may appear like a signet ring when the 

 vacuole has attained a large size, so that the nucleus and the 

 remainder of the cytoplasm appear to have been crowded to- 



[24] 



