Glycogenic function of the liver / by Howard Townsend.

  • Townsend, Howard, 1823-1867.
Date:
1864
Catalogue details

Licence: Public Domain Mark

Credit: Glycogenic function of the liver / by Howard Townsend. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    has not yet been determined from what element of the blood it is elaborated. There is a strong probability that the production of this liver sugar takes place at the expense of the protein compounds, and that it is the chief means through which the products of the dis- integration of muscular and other albuminous tissues are made available for the maintenance of animal heat by means of the combustive process. Of the character of the sugar thus produced in the liver little is yet definitely known, but it would appear far to surpass even glucose in the readiness with which it is carried off by the respi- ratory process, for according to Bernard, twelve grammes may be injected into the blood with no more effect upon the urine than is produced by 2.5 grammes of glucose, or of 0.5 of cane sugar. The word Glycogene, which gives the name to this function of the liver, is derived from two Greek words, yXvicvg, sweet; yeveacg, generation. The glycogene which is elaborated by the liver, is the first formation in the hepatic tissue, which secondly becomes converted into liver sugar by a process of catalysis. This glycogenic matter is regarded as intermediate in its nature and properties between hydrated starch and dextrine, according to Pelouze its ultimate composition is : ^12 -H-12 *~M2- If this glycogene be mingled with human saliva, at a tempera- ture of 100° F., the mixture will be found to reduce the salts of copper just as glucose will, proving that the glycogene has been converted into sugar by a catalytic process, just as vegetable starch would be changed under like circumstances. Glucose is the term now commonly employed in chem- istry for grape, fruit, starch and honey sugar, a variety of sugar occurring naturally in many vegetable juices. It differs from cane sugar in being much less soluble in water, and also less dis- posed to crystallize, and if it be injected into the blood vessels it does not pass off to an equal extent by the kidneys. Its chemi- cal composition is: CM H14 014, or C18 H1s 0» + 2 HO. Cane sugar, Sucrose, the chemical formula of which is : C18 H9 09 + 2 HO, is chiefly obtained from the sugar cane. If it be injected in any considerable amount into the general circulation, it is neither assimilated nor is it removed by the combustive process; but