378 THE LIVER. 



blood we have come to the general conclusion that when only the stasis 

 and other disturbing influences of the operation are prevented, the blood 

 of the liver veins, if at all, is only slightly richer in sugar than the blood 

 of the portal vein. 1 



The circumstance that the blood-sugar rapidly sinks to ^-J of its 

 original quantity, or even disappears when the liver is cut out of the cir- 

 culation, indicates a vital formation of sugar in the liver (SEEGEN. BOCK 

 and HOFFMANN, KAUFMANN, TANGL and HARLEY, PAVY). In geese 

 whose livers were removed from the circulation, MINKOWSKI found no 

 sugar in the blood after a few hours. On removing the liver from 

 the circulation by tying all the vessels to and from the organ, the 

 quantity of sugar in the blood is not increased (ScHENCK 2 ). An 

 important proof of the possibility of a vital formation of sugar from 

 the liver glycogen lies in the fact that we shall learn below of certain 

 poisons and operative changes which may cause an abundant elimina- 

 tion of sugar, but only when the liver contains glycogen. 



A vital formation of sugar from the liver glycogen is now generally 

 accepted. Most investigators consider this as an enzymotic transforma- 

 tion of the glycogen by means of the liver diastase, while certain inves- 

 tigators such as DASTRE, NOEL-PATON, E. CAVAZZANI, McGuiGAN and 

 BROOKS 3 and others explain it by a special activity of the protoplasm. 



The relation of the sugar eliminated in the urine under certain 

 conditions, such as in diabetes mellitus. certain intoxications, lesions 

 of the nervous system, etc., to the glycogen of the liver is also an import- 

 ant question. 



It does not enter into the plan and scope of this book to discuss in 

 detail the various views in regard to glycosuria and diabetes. The 

 appearance of dextrose in the urine is a symptom which may have essen- 

 tially different causes, depending upon different circumstances. Only 

 a few of the most important points will be mentioned. 



The blood always contains about the average of 1 p. m., while the 

 urine has in it at most only traces of dextrose. When the quantity of 

 sugar in the blood rises to 3 p. m. or above, then sugar passes into the 

 urine, but not always. 4 The kidneys have the property to a certain 



le diabete, Paris, 1877; Seegen, Die Zuckerbildung im Tierkorper, 2. Aufl., Berlin, 

 1900; M. Bial, Pfliiger's Arch., 55, 434. 



Seegen, Die Zuckerbildung, etc., and Centralbl. f. Physiol., 10, 497 and 822; 

 Zuntz, ibid., 561; Mosse, Pfliiger's Arch., 63; Bing, Skand. Arch. f. Physiol., 9. 



2 Seegen, Bock, and Hoffmann, see Seegen, I.e.; Kaufmann, Arch.de Physiol. (5), 

 8; Tangl and Harley, Pfluger's Arch., 61; Pavy, Journ. of Physiol., 29., Minkowski, 

 Arch. f. exp. Path. u. Pharm., 21; Schenck, Pfluger's Arch., 57. 



3 McGuigan and Brooks, Amer. Journ. of Physiol., 18. In regard to the literature 

 see Pick, Hofmeister's Beitrage, 3, 182. 



4 See Mohr, Zeitschr. f. exp. Path. u. Therap., 4. 



