THE PITUITARY BODY 



be carried much farther before definite statements can be 

 made concerning either their number or their other biological 

 effects (e.g., on the mammary glands or adrenal cortices). 

 However, a number of other methods has been employed to 

 learn how regulation by the anterior pituitary is effected. 

 Carbohydrate metabolism has been studied after hypophy- 

 sectomy; in such studies, epinephrine or insulin also has been 

 used. The remarkable amelioration of diabetes which follows 

 the removal of the hypophysis from depancreatized animals 

 has received further attention. The most important inter- 

 relationships with other glands of internal secretion are those 

 with the pancreas and adrenal glands. 



The anterior pituitary appears to be necessary for the ab- 

 sorption of glucose at a normal rate from the digestive tract; 

 however, there is no evidence that a specific hormone, such as 

 that affecting the metabolism of carbohydrate after absorp- 

 tion, alters the process of absorption. The "diabetogenic" 

 hormone of the anterior pituitary probably prevents the 

 prodigal waste of important, but sometimes small, carbo- 

 hydrate reserves which, for example, are maintained in spite 

 of fasting. An animal isolated from all sources of the hor- 

 mone (as after hypophysectomy) and dependent upon its 

 own reserves of food, dangerously uses up all available carbo- 

 hydrate. It is able readily to mobilize the glycogen of both 

 the liver and striated muscle and to oxidize glucose. Perhaps 

 another important metabolic function of anterior pituitary 

 secretion is to facilitate the new formation of carbohydrate 

 from both fat (glycerol) and protein. 



The diabetogenic hormone can be viewed as an antagonist 

 of insulin, the internal secretion of the pancreas. There is evi- 

 dence that this antagonism is indirect and depends upon the 

 support of adequate adrenal function. However, there is not 

 complete agreement that bilateral adrenalectomy prevents 

 the disturbing effects of anterior pituitary extract on carbo- 

 hydrate metabolism — e.g., hyperglycemia in the dog. On the 

 other hand, the glycosuria which follows the injection of an- 



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