1893.] On Hepatic Glycogenesis. 315 



A. Influence of Destruction of the Morphological Structure of the Liver 



Cells on Hepatic Amylolysis. 



The liver of a rabbit, freshly killed and bled, was divided into three. 

 One part, A, was pounded in a mortar with, fine clean sand, and was 

 then kept in salt solution at 40 C. The second part, B, roughly 

 minced, was placed in a similar solution. The third part, C, was 

 used to determine the initial amount of glycogen. At the end of some 

 time A and B were boiled, and the glycogen extracted. The follow- 

 ing two experiments show that destruction of the structure of the liver 

 cells very greatly inhibits the conversion of glycogen. 



A. B. C. Time. 



5-48 4-41 5-97 1 hr. 48 m. 



5-061 2-336 5-267 4 8 



B. Structural Changes in Liver Cells of Excised Liver kept under the 



Conditions above described. 



The histological methods employed are described and the structure 

 of the normal liver cell is considered. In the liver kept in salt solu- 

 tion at 40 C. as above described the protoplasm network becomes 

 more apparent and then breaks up and tends to collect round the 

 nucleus. The nucleus, somewhat later, loses its distinct outline 

 and its network and stains diffusely. Finally, it breaks up. 



These changes begin to manifest themselves usually within the first 

 hour, and are often not completed even at the end of twenty-four 

 hours. 



The conversion of glycogen seems thus divisible into two periods. 



1. An early period of rapid conversion occurring before obvious 



structural changes appear in the liver cells. 



2. A late period of slow conversion after the changes above 



described have developed. 



The rapid and extensive conversion appears to be inhibited by 

 destroying the structure of the liver cells. 



Further to elucidate the nature of these changes, the influence of 

 various factors upon them was studied. 



I. Temperature. The possibility of distinguishing between zymins 

 and living ferments by the influence of temperature of over 60 C. in 

 destroying the latter, but not the former, is discussed, and it is con- 

 cluded that it has a distinct, though restricted, value. So far as they 

 go, the following experiments, showing that exposure for one hour to 

 a temperature of 60 C. inhibits, but does not completely stop, 

 hepatic amylolysis,* favour the view that the process is dependent 

 on a living ferment rather than on a zymin. 



* " Hepatic amylolysis " is used throughout this paper as an abbreviation fo 

 " the conversion of hepatic glycogen to sugar." 



VOL. LIT. 7. 



