GLYCOGEN IMPOVERISHMENT 225 



mobilization of sugar in the liver is presided over by nervous 

 influences, following the evidence given by the gifted Claude 

 Bernard when he announced his " sugar puncture " and 

 showed that injury of the floor of the fourth ventricle is 

 followed by glycosuria. The same thing has since then been 

 noted after divers wounds in the general field of the nervous 

 system; and the present belief is that the function of the 

 liver in carbohydrate metabolism is under the regulating 

 influence of a " sugar centre ' ' in the medulla oblongata, the 

 vagus nerves carrying centripetal impulses and the splanch- 

 nics centrifugal. According to Ernst Freund and H. Pop- 

 per in the dog an abundant deposit of glycogen can be 

 obtained in the liver from intravenous injections of sugar, 

 only if all cerebral stimulation is eliminated, either by 

 narcosis or by interruption of the centrifugal nervous 

 paths. 12 



Production of Glycogen Impoverishment in the Body. 

 Besides muscular activity there are a great number of other 

 physiological and pathological factors known which may pro- 

 duce reduction in the body supply of glycogen. All forms of 

 inanition should be prominently named in this connection 

 in which loss of sugar from the economy as in pancreatic, 

 phloridzin or adrenin diabetes may give rise to such serious 

 exaggeration as to impoverish the system of its carbohy- 

 drates. Here, too, should be classed increased heat produc- 

 tion, as seen in fever and, too, in exposure to cold; and, 

 finally the influence of local hepatic lesions (as from ligation 

 of the hepatic duct or from injection of acid into the bile 

 duct) and of intoxications (as from phosphorus, arsenic, 

 chloroform, amyl nitrite and many others) should be added. 

 Among the poisons which cause degeneration of the liver 

 parenchyma and disturb its glycogen function, according to 

 Asher, 13 lymphagogues, like peptone, extract of crab-muscle 

 and leech-extract, are to be included. 



12 E. Freund and H. Popper, Biochem. Zeitschr., 41, 56, 1912. 

 13 L. Asher and Kusmine (Berne), Zeitschr. f. Biol., 46, 554, 1905. 

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