PROTEINS OF THE LIVER. 361 



Even though the liver is of assimilatory importance and purifies the 

 blood coming from the digestive tract, it is at the same time a secretory 

 organ which eliminates a specific secretion, the bile, in the production 

 of which the red blood-corpuscles are destroyed, or at least one of their 

 constituents, the haemoglobin. It is generally admitted that the liver 

 acts contrariwise during foetal life, at that time forming the red blood- 

 corpuscles. 



There is no doubt that the chemical operations going on in this 

 organ are manifold and must be of the greatest importance to the 

 organism. Our knowledge on this subject has been essentially advanced 

 by recent investigations, but nevertheless it must be admitted that 

 we know little of the character and extent of these changes. Among 

 the products of these chemical processes there are two which are 

 especially important and must be treated in this chapter, namely, the 

 glycogen and the bile. Before the study of these products is taken up, 

 a short discussion of the constituents and the chemical composition of 

 the liver is necessary. 



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 l ) . 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 PLOSZ. 

 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 nucleoalbumin 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 pos- 

 sessed 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 

 (0.28-1.3 per cent) of this globulin as well as the insolubility of the pre- 



Vamossy, Centralbl. f. Physiol., 18, and Rothberger, Wien. klin. Wochenschr., 1905, 

 Rothberger and Winterberg, Biochem. Centralbl., 4. 



1 Morishima, Arch. f. exp. Path. u. Pharm., 43; Magnus-Levy, Hofmeister's Beitrage,2. 



2 Plosz, Pfluger's Arch., 7; Halliburton, Journ. of Physiol., 13, Suppl. 1892. 



