THE LIVER FORMATION OF AMYLOID SUBSTANCE. 489 



401. The use of the amyloid substance developed iu the Liver is involved 

 in the greatest obscurity. By the earlier observers it was thought that it was 

 immediately reconverted into sugar, and undergoing combustion in its passage, 

 through the Lungs, became subservient to the maintenance of animal heat. 

 Various arguments have, however, been justly urged by Dr. Pavy against 

 this view, and he is himself disposed to regard its production as representing 

 the first step of assimilation of the starchy and saccharine elements of our food ; 

 and as these elements are known to proceed on into fat, he thinks there are 

 grounds for believing that amyloid substance occupies an intermediate posi- 

 tion between the two. The process of assimilation, he believes, may go on 

 to the production of fat in the liver, or it may be that it stops short at the 

 formation of another principle which escapes from the liver, and is elsewhere 

 transformed into fat, or into the resinoid matter of the bile. In accordance 

 with this view are the researches of Tscherinoff, who, obtaining similar results 

 to those of Dr. Pavy in regard to the amyloid substance, noticed also that the 

 use of food containing much hydrocarbonaceous matter, as sugar, greatly in- 

 creased the proportion of fat in the liver. Two theories have been advanced 

 to explain why the amount of glycogen in the liver is increased after the use 

 of the carbohydrates. On the one hand, it may be said that the carbo- 

 hydrates are more or less completely converted into glycogeu within the 

 liver, and that they are stored up iu that organ ; l and on the other it is 

 maintained that the carbohydrates being readily oxidizable seize upon the 

 oxygen of the blood and spare the glycogen derived from some other source. 2 

 The probabilities seem iu favor of the former view. In regard to the origin 

 of glycogen from oleaginous compounds, the experiments of Bernard, and 

 McDonnell, and Luchsinger with fat dietaries seemed to show that this diet 

 is unfavorable to the formation of glycogen, and even Salomon, whose recent 

 experiments 3 are not quite in accordance with those of his predecessors, shows 

 that the proportion of glycogen is very much less on a fat than upon a saccha- 

 rine diet, and about half as much as upon a gelatin diet. The concordant 

 results of Weiss, Luchsiuger, and Salomon show that glycogen is abundantly 

 formed, when glycerin is either administered alone in a diluted state or given 

 with the food. Experiments with soap diet have been undertaken by Sal- 

 omon, but have not enabled him to determine whether the glycogen in neutral 

 fat diet proceeds from the glycerin it contains. The circumstance that the 

 blood which enters the Liver is rich in fibrin and albumen, whilst that which 

 leaves it is poor in these materials, has led Dr. McDonnell to suggest it as 

 probable that these materials break upinto secondary hydrocarbonaceous com- 

 pounds, which are partly eliminated by the bile-ducts, and are partly stored up 

 as glycogeu ; and into nitrogenous compounds, which reunite with the hydro- 

 carbonaceous amyloid substance, and leave the liver as a newly-formed 

 protein compound, partly perhaps as globulin, and partly as a material re- 

 sembling casein or albuminose. More recently, Dr. \V. Ogle 4 has advanced 

 a similar view, and holds that before leaving the liver glycogen unites with 

 some albuminous compound which enters the blood-corpuscles and from them 

 is transferred to the muscles, where it undergoes decomposition with lactic 



1 See Pavy, loc. cit. ; Tscherinoff, loc. cit. ; Dock, Pfluger's Archiv, Bd. v, p. 57. 



2 Scheremetjewski (Ludwig's Arbeiten, 1869, p. 154) and Weiss (Sitz. d. VVien. 

 Akad., Bd. Ixvii, abth. 3) advocate this view, on the ground that after the adminis- 

 tration of glycerin the proportion of glycogen in the liver is notably increased, 

 glycerin being a substance not likely to be converted into glycogen. Both Kiihne 

 and Luchsinger (Pfliiger's Archiv, 1873, Bd. viii, p. 289) have shown that this is 

 an assumption unwarranted by facts. 



3 Virchow's Archiv, Bd. Ixi, 1874, p. 854. 



4 See St. George's Hospital Eeports, vol. iii, 18G8, p. 149. 



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