FORMA TION OF GL YCOGEN. 92 1 



noticed that the amount of nitrogen in the urine goes hand in hand with 

 the amount of sugar excreted. 1 Further, it is found that if the glycogen 

 in the body be reduced as much as possible by a prolonged period of 

 starvation, followed by excessive muscular action, such as is caused by a 

 dose of strychnine, the administration of phloridzin will still cause 

 glycosuria; much more sugar appearing under these circumstances in 

 the urine than can be accounted for by any glycogen which might remain 

 either in the liver or any other tissues of the body. It seems, therefore, 

 clear that the sugar must have been derived from proteid ; in this case 

 the proteids of the body itself. It may further be mentioned that Pick 2 

 has found that if the liver be rendered functionless by injecting dilute 

 sulphuric acid into the bile ducts, its glycogen disappears in twelve 

 hours, but phloridzin still produces glycosuria, although other agents 

 which usually cause glycosuria, such as carbon monoxide, fail to produce 

 this effect. As with the glycosuria produced by phloridzin, so also with 

 severe cases of natural diabetes in man, there appears to be no doubt 

 that a direct formation of sugar from proteid may occur without any 

 formation of glycogen. It may be supposed with some probability that 

 such a direct formation of sugar (mainly by the liver, for phloridzin 

 diabetes is produced in the absence of the liver), 3 but also by other organs; 4 

 and its passage into the blood may occur to some extent normally ; that 

 in fact a part of the carbohydrate produced from proteid may be at 

 once passed into the blood in the form of dextrose, and a part further 

 synthetised into glycogen and stored as such. 5 We might then explain 

 phloridzin diabetes, and possibly certain severe cases of natural diabetes, 

 by supposing that the further synthesis into glycogen is in some way 

 interfered with, so that an excess of the carbohydrate formed is passed 

 into the blood in the form of sugar. 



It must, however, be stated that the production of the severest forms 

 of diabetes above mentioned, and also that produced by removal of the 

 pancreas (see p. 927) and by the sugar-puncture (see p. 926), is still exceed- 

 ingly obscure. According to v. Mering and most other observers, there 

 is a fundamental difference between the diabetes caused by phloridzin 

 and that produced by pancreatic removal or sugar-puncture, in that in 

 the former there is no excess of sugar in the blood, in fact the amount 

 may be less than normal, 6 whereas in the two last-mentioned forms the 



1 v. Mering, loc. tit., found the proportion of urea to sugar in phloridzin diabetes = 1 : 2, 

 in cases of natural diabetes = l : 1. See also Moritz and Praussnitz, Ztschr. f. BioL, 

 Munchen, 1891, Bd. xxvii. S. 81 ; Praussnitz, loc. Git.; Cremer and Hitter, Ztschr. f. BioL, 

 Miinchen, 1893, Bd. xxix. S. 256. v. Mering and Minkowski (Arch. f. exper. Path. u. 

 PharmakoL, Leipzig, 1889, Bd. xxvi.) found the proportion of sugar to nitrogen =3: 1 in 

 pancreatic diabetes. 



2 Arch. f. exper. Path. u. PharmakoL, Leipzig, 1894, Bd. xxxiii. S. 305. 



3 Thiel, Arch. f. exper. Path. u. PharmakoL, Leipzig, 1887, Bd. xxiii. 



4 Cornevin (Compt. rend. Acacl. d. sc., Paris, 1895, tome cxvi. p. 263) has shown that 

 phloridzin causes a marked increase in the amount of sugar eliminated in the milk. 



5 Seegen states that he obtained a formation of sugar (in excess of that produced by 

 transformation of any glycogen present) in a mixture of chopped liver and arterial blood, to 

 which peptone had been added, and even with the addition of fat in place of peptone. 

 But his results have not been confirmed by other workers. Cf. Bohm u. Hoffmann, 

 Arch. f. d. ges. PhysioL, Bonn, 1880, Bd. xxiii.; Girard, ibid., Bd. xvi. S. 294; 

 Neumeister, Ztschr. f. BioL, Miinchen, 1890, S. 346. The possibility of the formation of 

 carbohydrate from fat in animals, although not experimentally proved, must not be 

 ignored. For there is clear evidence that such a transformation may occur in germinating 

 seeds of plants (Sachs, "Text-Book of Botany," transl. by Bennett and Thiselton Dyer, 

 1875, p. 638), and if plant bioplasm is capable of effecting the transformation, animal 

 bioplasm might also be expected to have a similar power. 



6 No diminution but an increase in the amount of blood-sugar was found by Pavy to 



