CHAPTER V 



THE INTERNAL SECRETION OF THE LIVER 



As stated in a preliminary manner above, the liver has, in 

 addition to the formation of the bile, several important meta- 

 bolic duties. The chief of these, the glycogenic function, has 

 already been alluded to, and although to it was first applied 

 the name " internal secretion," we shall not treat of the subject 

 any further, for the reasons that the process is a highly special 

 one, and that it would occupy too much space to treat of the 

 enormous literature of the subject. 



It is possible that some of the ductless glands which are 

 usually supposed to act only on the pancreas may act on the 

 liver by means of the sympathetic nerves. 



A word or two ought to be said about the duty of the liver 

 in rendering innocuous the end-products of protein metabolism. 

 There are many facts which point to the significance of 

 the liver in the production of urea. In the dog, when the 

 arterial blood -supply is completely cut off from the organ, 

 the ratio of the urea to the total nitrogen of the urine falls 

 considerably. The liver can manufacture urea not only out 

 of NH 3 , but also from other nitrogenous bodies. So far as 

 the production of urea from ammonia compounds is con- 

 cerned, the process involves an antitoxic action, the dis- 

 tinctly poisonous ammonia being transformed into the com- 

 paratively harmless urea. This is what Biedl calls a " negative 

 internal secretion," and what has already been referred to as 

 "internal excretion" (pp. 14, 16). There are, however, 

 probably several sources of urea in the body, and several 

 distinct places of origin. 



The liver is stated to be antitoxic also for other poisons, such 

 as strychnine and nicotine, but not for atropine and curare. 

 According to Charrin, the protective action of the liver in 



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