PRODUCTION OF SUGAR IK THE LIVER. 317 



sequently shown to be correct, that the liver contains a 

 peculiar principle, slightly soluble in water and capable 

 of transformation into sugar. We have given rather a de- 

 tailed account of this observation, because some authors 

 have attributed the discovery of the glycogenic matter to 

 Hensen. Hensen confirmed Bernard's observations, in 1856, 

 and described the insoluble substance rather more fully. 1 

 In 1857, Bernard studied the mechanism of the glycogenic 

 function more closely, and completed his description of the 

 glycogenic matter. 3 



Glycogenic Matter (C 12 H ia O 12 ). In its composition, re- 

 actions, and particularly in the facility with which it under- 

 goes transformation into sugar, glycogenic matter bears a 

 very close resemblance to starch. It is described by Pavy 

 under the name of amyloid matter, 8 a name which is applied 

 to it, also, by Rouget. 4 It is insoluble in water, and, by vir- 

 tue of this property, may be extracted from the liver after 

 the sugar has been washed out. The following is the method 

 for its extraction proposed by Bernard : 6 



The liver of a small and young animal, like the rabbit, 

 in full digestion, presents the most favorable conditions for 

 the extraction of the glycogenic matter. The liver is taken 

 from the animal immediately after it is killed, is cut into 

 thin slices, and thrown into boiling water. When the tissue 

 is hardened, it is removed and ground into a pulp in a mor- 

 tar. It is then boiled a second time in the water of the 



1 HENSEN, Ueber die Zucherbildung im thierischen Organismus. SCHMIDT'S 

 Jahrbuther, Leipzig, 1857, Bd. xciii., S. 15; taken from Verhandlungen derphy.- 

 med. Gcs. zu, Wurzb., 1856, Bd. vii., S. 219. 



2 BERNARD, Sur le mechanixme physiologique de la formation du sucre dans le 

 foie. Comptes rendus, Paris, 1857, tome xliv., p. 578. 



3 PATY, Researches on the Nature and Treatment of Diabetes, London, 1862, 

 p. 26, et seq. 



4 ROUGET, Des substances amylo'ides ; de leur role dans la constitution dex tis- 

 sus des animaux. Journal de la physiologic, Paris, 1859, tome ii., pp. 83, 308. 

 Rouget calls the glycogenic matter, or animal starch, zoamyline. 



6 BERNARD, Liquides de Vorganisme, Paris, 1859, tome ii., p. 119. 



