ADRENALS 667 



operations required for the extirpation of the hypophysis from its 

 sheltered position within the skull, and it will not be wondered at that 

 complete harmony has not been attained as to the consequences of its 

 removal. The best evidence at present is to the following effect: 



When the pituitary body is completely removed, death speedily 

 and invariably ensues, in dogs, on the average within twenty-four 

 to forty-eight hours. Puppies often live as long as two or three 

 weeks. The much longer periods of survival occasionally witnessed 

 are due to failure to remove some small portion of the hypophyseal 

 epithelium. On the day after the operation the animals may be 

 able to walk about, to eat and drink, and may show an interest in 

 their surroundings. The temperature, pulse, and respiration at 

 this time may be normal. Soon, however, they become lethargic, 

 then comatose, with characteristically incurved spine, slow respira- 

 tion, with long-drawn inspiration, a feeble pulse, perfectly limp 

 muscles, and often a subnormal temperature, and the appearance 

 of sugar in the urine. This deep coma passes into death, with no 

 perceptible transition, and without a struggle (Paulesco, Gushing). 

 The ablation of a part of the cortical substance of the anterior 

 (epithelial) lobe of the hypophysis is compatible with permanent 

 survival, and gives rise to no symptom of disorder. The same is 

 true when only the posterior lobe is removed. This does not seem 

 to be followed by any recognizable symptoms. In some animals, 

 however, kept tinder observation for long periods after partial 

 removal of the anterior lobe, a marked tendency to accumulate 

 fat has been noted, accompanied by hypoplasia of the generative 

 organs in adults or the persistence of the infantile condition in 

 immature animals. On the other hand, complete removal of the 

 anterior lobe causes death, just as if the whole gland had been 

 taken away. Of all the structures included in the pituitary body, 

 the most important from the functional point of view appears to be 

 the superficial layer of the anterior lobe. 



Mere separation of the stalk of the hypophysis may produce 

 effects sometimes as serious as those of total removal of the gland, 

 probably owing to the disturbance caused in the circulation. It is 

 stated, indeed, by some observers that the vulnerable point is the 

 base of the infundibulum, and that if this is not injured extirpation 

 of the hypophysis is not incompatible with continued existence, 

 and that in adult animals the resultant changes are only slight, 

 although much more pronounced, especially as regards the disturb- 

 ances in metabolism and development in young animals. It has 

 been asserted that the pituitary undergoes (compensatory ?) hyper- 

 trophy after thyroidectomy. Some observers have accordingly 

 assumed a similarity of function for these organs. It has even been 

 stated that the production of colloid material by the cells of the pars 

 intermedia is increased, and that colloid accumulates in the 



