308 PHYSIOLOGY CHAP. 



Lastly, he made important observations on the exothermal 

 phenomena in the liver under all experimental conditions in 

 which an increase of hepatic glycogenesis takes place : (ct) In 

 asphyxia, according to Morat and Dufour, so soon as there is hyper- 

 glycaemia, the temperature of the liver rises. (5) The same is 

 found during stimulation of the vagi when, according to Butte, 

 hepatic glycogenesis is exaggerated, (c) When, after cardiac 

 paralysis and suspension of circulation, the formation of sugar 

 becomes more active, while all other organs are cooling more or 

 less rapidly, the liver exhibits a post-mortem rise of temperature, 

 lasting 10-20 minutes, of half a degree or even more, (d) In 

 fasting or very emaciated animals the asphyxial and post-mortem 

 rise is almost or entirely absent, since, as we have seen, glyco- 

 genesis is limited by scarcity of glycogen. The opposite occurs 

 with well-nourished animals. () In animals into which curari 

 or atropine, or methyl violet in suitable doses, is injected intra- 

 venously, neither asphyxial hyperthermia nor hyperglycaemia is 

 perceptible. With injection of methyl violet, post-mortem glyco- 

 genesis is also suspended, in correspondence with which fact the 

 temperature of the liver falls rapidly like that of the other organs. 



From these facts, as a whole, it is evident that the hepatic 

 glycogenesis by which glucose is formed from the glycogen and 

 poured into the blood, is accompanied by phenomena highly 

 similar to those observed during the secretion of other glandular 

 organs. 



X. It now remains to see from what constituents the glycogen 

 which serves for the secretion of glucose originates, and whether 

 other tissues besides the liver are capable of forming or storing up 

 glycogen as a reserve material. 



In the first place, it must be observed that the amount of 

 glycogen accumulated in the liver varies considerably with 

 different animals, and also in the same animal under different 

 conditions of nutrition and diet. Pavy, in dogs which had been 

 fed for a long time on bread and potato, found 15 per cent 

 glycogen in the liver. In rabbits led on starchy foods and 

 beetroot it amounted to a maximum of 2*7 per cent. Supposing 

 the human liver to be capable of accumulating 10 per cent of 

 glycogen, and the weight of the liver to be 1500 grms., we should 

 have 150 grms. glycogen stored up in this organ. 



That the glycogen content of the liver depends essentially on 

 diet has been convincingly proved by the fact that during an 

 absolute fast the glycogen wholly or almost entirely disappears 

 from the liver, in rabbits after 5 days, in dogs after 2-3 weeks. 

 According to Pfliiger, the glycogen never disappears completely, 

 even in rabbits ; in dogs a certain amount remains even after a 

 fast protracted for weeks. 



When an animal that has been almost entirely deprived of its 



