OPERATIONS ON THE PITUITARY 69 



Removal of small portions of the anterior lobe Effects of 

 causes no changes in the genitalia. The bitches came moV ai of pars 

 on heat, and one had coitus without being fertilized. twenttalia 



In all my experiments portions of the uterus and of 

 one ovary were removed a few days before the operation 

 on the pituitary, in order that I might have accurate 

 controls in regard to subsequent changes in these organs. 



EFFECTS OF REMOVAL OF A PORTION OF THE PARS 

 ANTERIOR ON THE OTHER HORMONOPOIETIC ORGANS 



It has been noted by Cushing and others that there Effects of 

 is a remarkable degree of hyperplasia in the thyroid movai oTpars 

 after partial removal of the anterior lobe. This con- the^roid 

 dition is said to subside eventually, and to be super- 

 seded by a considerable colloid formation, apparently 

 with the disappearance of epithelial activity. I was 

 unable to recognize any definite or constant change 

 in the thyroid after partial removal of the anterior 

 lobe of the pituitary, either in so short a period as 

 36 hours or after so long a time as 210 days subsequent 

 to operation. Changes no doubt do occur, but in an 

 organ of so variable an appearance in normal circum- 

 stances it is very difficult indisputably to demonstrate 

 small alterations in epithelial activity and colloid 

 formation. 



Partial removal of the pars anterior is said to lead to Effects of 

 hypertrophy of the thymus, just as the condition of movafoTthe 

 hypohypophysism is often associated with enlargement pars anterior 

 of the thymus. I found that many months after partial thymus. 

 removal of the anterior lobe the thymus is as well 

 developed as at a much earlier period of life, the 

 epithelial aggregations, known as HassalPs corpuscles, 

 being particularly prominent and unchanged. 



According to Cushing 1 , partial removal of the pars partial re- 

 anterior is followed by hyperplasia and lipoid vacuola- p^anferior 

 tion of the cells of the zona fasciculata. In my own on tJ j e su P ra - 



renals. 

 1 Cushing, H., The Pituitary Body and Its Disorders, 1912. 



