It has been shown by several authors that of the tests of hepatic function one of the most reliable is the so-called hippuric acid test, introduced by Quick1 in 1933. This test is based on the response of the liver to benzoic acid administered as sodium benzoate. When sodium benzoate is either ingested or injected intravenously, the benzoic acid radical is conjugated with aminoacetic acid in the liver to form hippuric acid, which is excreted through the kidneys.
The literature concerning the synthesis of hippuric acid has been reviewed elsewhere,2 and further review will not be attempted here.
From a practical clinical viewpoint it may be assumed that most of the hippuric acid is formed in the liver, although, as is well known, the synthesis of hippuric acid occurs in dogs even after the removal of the liver.3
We did not study the renal function in our