784 JAUNDICE. [BOOK n. 



It has been supposed that these cases afford proof that the bile 

 may be formed elsewhere than in the liver. In face however of the 

 arguments brought forward in the preceding paragraphs, they cannot 

 be accepted as proof that the normal formation of bilirubin is so 

 carried on ; nor is there any evidence to shew that in these cases 

 bilirubin is formed on a plan wholly different from the normal. 

 The absence of bile-acids from the urine in these cases has been 

 accounted for by supposing that they are destroyed, changed in 

 their transit through the blood stream ; but this does not seem 

 very satisfactory. And a different explanation seems possible. 

 We may suppose that in the cases in question the metabolic 

 activity of the hepatic cells is modified, and, further, so modified as 

 while affecting largely the formation of bile salts and other 

 functions of the hepatic cells, only partially to affect the formation 

 and discharge of bilirubin. That in acute yellow atrophy the 

 functions of the cells are greatly affected is not only indicated 

 by post-mortem histological appearances, but is also shewn, as we 

 shall presently have occasion to point out, by the substitution of 

 leucin and tyrosin for urea in the urine. 



481. The question may be asked, Is the secretion of bile 

 independent of or in some way or other connected with the 

 glycogenic activity of the cells ? To this we cannot at present 

 give a definite answer. In some of the invertebrata the cells in 

 the organ, called a liver, which manufacture glycogen, are distinct 

 from those which secrete bile or other digestive juices ; and it 

 might be inferred that in the vertebrate the two actions though 

 taking place, as they certainly do, in the same cell, take place 

 apart and distinct. There are facts which seem to indicate 

 that the two are intimately connected; but we have as yet no 

 exact knowledge concerning the matter. It has been urged 

 that the portal blood is chiefly concerned with the formation of 

 glycogen, and the blood of the hepatic artery with the secretion 

 of bile; but there is no adequate support of this view. It 

 must be remembered moreover that, in addition to the for- 

 mation of glycogen and the secretion of bile, other metabolic 

 events, especially affecting proteid or at least nitrogenous con- 

 stituents of the body, are also taking place; and to these we 

 must now turn. 



