CHAPTER XIII 

 THE PITUITARY BODY (continued) 



Effects of Complete Removal: Hypophysectomy 



A large number of experiments have been made with the view of de- 

 termining the nature of the symptoms which follow removal of the 

 pituitary. The results of these have been somewhat conflicting in character 

 — due in some measure to the differences of method employed to arrive at 

 the position of the organ, which is obviously a difficult procedure, deeply 

 placed as it is at the base of the brain. Thus, while one set of operators 

 (e.g. Horsley and Handelsmann, and Aschner) have preferred to approach 

 it (in animals) through the buccal cavity and basis cranii, in order to avoid 

 disturbance of the brain, others (e.g. Paulesco, Cushing, Biedl) have not 

 hesitated to attack it through a large aperture in the side of the skull, 

 another similar aperture being made on the opposite side so as to enable 

 the hemispheres to be pushed over in order to obtain a good view of the 

 gland ; in some animals, such as the dog, the organ can be got at without 

 much difficulty by this procedure. The former method has the dis- 

 advantages (1) that the operator is working at the bottom of a deep pit 

 from the walls of which blood is constantly oozing so as to obscure the parts, 

 and (2) that it is impossible to secure asepsis. By the use of the lateral 

 method these disadvantages are for the most part avoided, but it has been 

 alleged that the serious results which are described as following removal 

 of the organ by this operation are due to shock and paralysis caused by 

 the unavoidable insult to the brain. 



Effects of Complete Removal. — Paulesco was the first to state definitely 

 that complete removal is in every case sooner or later fatal. This result 

 was obtained with animals from all classes of Vertebrata. Most of the 

 hypophysectomised mammals died within two or three days. He also 

 found that mere severance of the stalk connecting the pituitary body to 

 the base of the brain is fatal. Paulesco's statements were confirmed by 

 Harvey Cushing and his fellow-workers, who for the most part restricted 

 their experiments to dogs. They found that adult animals usually succumb 

 after total deprivation in from two to five days, whilst puppies survive 

 longer (ten to thirty days); they ascribe this difference to the greater 

 functional adaptability of accessory glandules which are probably present 

 in the roof of the pharynx in young animals. In all cases of long survival 

 a fragment of the gland, including some of the anterior lobe, was found 



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