CHEMISTRY OF THE LIVER. 



phuric acid glucoronic acid acts to hold the phenol bodies ; it 

 is usually present in traces in normal urine and is often greatly 

 increased pathologically. The glucoronates may be formed in 

 the liver along with the aromatic sulphates. In experiments 

 which have been carried out on the passage of the blood 

 through a liver the conjugate phenol bodies produced have 

 frequently been in excess of the amount called for by the sul- 

 phuric acid found; this excess may correspond in the main 

 with the glucoronic acid. 



The Synthesis of Uric Acid. The mode and place of the 

 formation of uric acid in the animal organism have been the 

 subjects of numerous investigations. In birds, serpents and 

 some of the mammals the excretion of nitrogen is largely in 

 the form of uric acid, and experiments have shown that it is, 

 in part at least, of synthetic origin. The excretion of uric 

 acid in birds is increased by doses of ammonium salts; with 

 the livers extirpated there is a decrease in the elimination of 

 uric acid and increase in excretion of ammonium compounds. 

 In a number of such observations the liver has been connected 

 with uric acid formation, and transfusion experiments, in 

 which blood containing ammonium lactate and certain other 

 compounds has been forced through the livers of geese, 

 pointed to the same kind of a synthetic conversion. For the 

 higher animals, however, a different formation has usually 

 been assumed, the oxidation of the xanthine bodies coming 

 from the breaking down of nucleins being looked upon as the 

 principal formative reaction. 



Comparatively recent experiments by several authors sug- 

 gest synthetic reactions as likewise possible. Wiener, for ex- 

 ample, mixed chopped beef liver with physiologic salt solution 

 and allowed the mixture to stand at the body temperature an 

 hour. The liquid was then pressed out and the uric acid in 

 it determined after some time in a given volume. To the 

 same volume of liver extract definite weights of urea and vari- 

 ous ammonium and sodium salts were added and the mixture 

 allowed to stand as before. In certain cases a very marked 



