382 THE LIVER. 



the formation of urea or uric acid (in birds) from ammonium salts, the 

 formation of etheral sulphuric acids and conjugated glucuronic acids 

 from the phenols produced in intestinal putrefaction and the recently 

 shown syntheses of amino-acids in the liver. On the other hand a 

 deamidation of amino-acids and purine bodies, hydrolyses, oxidations, 

 reductions and fermentative processes of various kinds occur in the liver. 

 Because of these diverse processes, the results of which we must espe- 

 cially mention the formation of bile as well as the fact that the liver is 

 introduced between the intestine and the general circulation, makes the 

 liver a central organ for metabolism. 



Among the numerous chemical processes which take place in the liver 

 there are especially two which give special interest to this organ, namely, 

 the formation of glycogen or the carbohydrate metabolism in the liver, 

 and the formation of bile. For this reason only these two processes will 

 be discussed in this chapter while the others will be discussed in other 

 chapters and in other connection. Before we begin to discuss these two 

 processes a short review of the constituents and the chemical com- 

 position of the liver seems to be appropriate. 



The reaction of the liver-cells is alkaline toward litmus during life, 

 but becomes acid after death, due to a formation of lactic acid, chiefly 

 fermentation lactic acid and other organic acids (MORISHIMA, MAGNUS- 

 LEVY 1 ). A coagulation of the protoplasmic proteins in the cells probably 

 takes place. A positive difference between the proteins of the dead 

 and the living, non-coagulated protoplasm has not been observed. 



The proteins of the liver were first carefully investigated by PL6sz. 

 He found in the watery extract of the liver an albuminous substance 

 which coagulates at 45 C. (globulin, HALLIBURTON), also a globulin 

 which coagulates at 75 C., a nuckoalbumin which coagulates at 70 C., 

 and lastly a protein body which is closely related to the coagulated albumins 

 and which is insoluble in dilute acids or alkalies at the ordinary tem- 

 perature, but dissolves on the application of heat, being converted into 

 an albuminate. HALLIBURTON 2 found two globulins in the liver-cells, 

 one of which coagulates at 68-70 C., and the other at 45-50 C. He 

 also found, besides traces of albumin, a nucleoprotein which possessed 

 1.45 per cent phosphorus and a coagulation-point of 60 C. POHL has 

 obtained an " organ plasma " by extracting the finely divided liver 

 which had previously been entirely freed from blood by washing with 

 8 p. m. NaCl solution, in which he was able to detect a globulin having 

 a low coagulation temperature. The very variable phosphorus content 



1 Morishima, Arch. f. exp. Path. u. Pharm., 43; Magnus-Levy, Hofmeister's Bei- 

 trage, 2. 



2 P16sz, Pfliiger's Arch., 7; Halliburton, Journ. of Physiol., 13, Suppl. 1892. 



