THE PITUITARY BODY 



of processes of unknown complexity. However, the potential 

 value of what can be learned is immense in its implications 

 not only to physiology but also to clinical medicine. 



The metabolism of fat, depending upon conditions, is 

 probably closely interrelated with that of carbohydrates. 

 Since little is known concerning the nature of the substance(s) 

 aifecting the metabolism of carbohydrates and fats which 

 can be extracted from or are secreted by the pars glandularis, 

 it is by no means clear whether or not one or more substances 

 is responsible for the effects, or, indeed, whether the effects 

 are due to a hormone to which another name has already been 

 given. Perhaps an anterior pituitary hormone which de- 

 presses the rate of catabolism of carbohydrate (and increases 

 the rate of protein anabolism) indirectly necessitates the 

 mobilization and oxidation of an increased proportion of fat, 

 so that ketogenesis is facilitated. The outstanding facts con- 

 cerning the effects of pituitary extract on the metabolism of 

 fat appear to be (i) large doses of anterior pituitary extract 

 bring about a deposition of fat in the liver which, in fasted 

 animals at least, is enriched at the expense of other tissues 

 and (2) anterior pituitary extract produces ketosis which 

 probably is associated with the changes described under (i). 

 (It is generally believed that acetone bodies are formed in 

 the liver.) It is of great interest that both of these changes 

 are said to be prevented by adrenalectomy, apparently be- 

 cause of the removal of the cortex. This, in turn, suggests 

 that an adrenal cortical stimulating substance is the pituitary 

 secretion affecting the metabolism of fats. 



There still is not a sufficiently large body of data to enable 

 one to discuss with any assurance the manner in which the 

 metabolism of proteins is influenced by secretion(s) of the 

 pars glandularis. It appears that hypophysial deficiency 

 probably is accompanied by increased catabolism of proteins 

 of endogenous origin and imperfect utilization of proteins of 



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