THE PITUITARY BODY 765 



lar tremors may appear, the respiration and pulse become slow, the back 

 arched, the temperature subnormal; and, usually within about forty- 

 eight hours, coma develops and the animal dies in this condition. When 

 the symptoms are less acute and death does not occur so early, it is 

 believed by Gushing either that small portions of the gland have been 

 left behind or that some vicarious activity of other organs has developed 

 to replace that of the pituitary. 



When only a part of the pituitary is removed either unintentionally 

 or intentionally, the symptoms are not nearly so acute, and the condition 

 is known as hypopituitarism. It is by a study of this condition that 

 most facts concerning the function of the anterior lobe have been learned. 

 When the operation is performed on young animals, they fail to grow 

 properly; the milk teeth and the lanugo are retained; the epiphyses 

 do not ankylose; the thyroid and thymus glands are enlarged; and the 

 cortex of the suprarenal and the sexual organs fails to develop. The 

 animal, though small, becomes very fat and may therefore increase in 

 weight. There is distinct evidence of mental dullness. From these 

 results it is concluded that the anterior lobe of the pituitary produces 

 autacoids having to do ivith the development of the skeletal and other 

 structures of the growing animal. That this autacoid is not derived from 

 the posterior lobe is evidenced by the fact that partial injury of this 

 lobe, or indeed its entire removal, is not followed by similar symptoms. 



Closer examination of the metabolic function in hypophysectomized 

 animals has shown that there is a marked depression in the respiratory 

 exchange of oxygen and carbon dioxide, and that the ability to metabo- 

 lize carbohydrate becomes heightened; that is to say, the animal with- 

 out developing glycosuria can tolerate a larger quantity of sugar than 

 the normal animal. This effect on carbohydrate metabolism may how- 

 ever be associated not so much with the function of the anterior lobe as 

 with that of the posterior, for, as we shall see later, Gushing and his 

 pupils have found that extract of the posterior lobe has a marked effect 

 on the assimilation limit of carbohydrate. 



Attempts have been made to graft the pituitary, especially the anterior 

 lobe, into various parts of the body. It has been found, however, that 

 within a few days the grafts atrophy and disappear unless there has 

 been complete removal of the pituitary itself, in which case the graft 

 may remain for a month or so and the otherwise fatal outcome of hypophy- 

 sectomy be warded off. Sometimes, where the graft has remained for a 

 longer time, it is said that a temporary increase in the growth of the 

 .animal has been noticed. 



Other observers have investigated the effects in normal animals of 

 continuous oral administration of pituitary substance or of subcutaneous 



