PANCREAS AND CARBOHYDRATE METABOLISM. 929 



stances, its amount, as in the case of phloridzin glycosuria, rises and 

 falls with the amount of nitrogen in the urine (see p. 921), it may 

 be assumed that it is derived in these cases also from the splitting of 

 proteids. 



The exact amount of the pancreas which it is necessary to leave in 

 order to prevent the occurrence of glycosuria cannot be exactly given, 

 but a comparatively small amount is sufficient. If somewhat less than 

 this minimum be removed, diabetes of a less severe type than that 

 following complete removal may occur. There is, however, a tendency 

 for it to become more severe in process of time, probably from a certain 

 amount of atrophy occurring in the pancreatic tissue which has been 

 left. 1 



Cause of pancreatic diabetes. It appears probable that the pancreas 

 exerts its influence upon carbohydrate metabolism, either by promoting 

 the formation of glycogen in the liver from the dextrose taken to it by 

 the portal blood, or by furthering the oxidation of dextrose in the tissues 

 generally. In either case the effect would be the prevention of the 

 accumulation of dextrose in the blood, so that the percentage of sugar 

 in this fluid would be kept down to its normal, small amount. Whether 

 this is brought about by the direct action of the organ upon dextrose 

 which reaches it with the blood, or whether it acts indirectly in promot- 

 ing the metabolism of dextrose by an internally secreted material, which 

 passes out from the organ into the blood and tissues, is a question which 

 it is impossible at present to give an answer to. Diabetes which results 

 from removal of the pancreas, is not necessarily due to an increased 

 glycogenesis from transformation of glycogen (although this is the cause 

 of the glycosuria which first makes its appearance), for it will continue 

 after the glycogen has completely disappeared from the liver and muscles. 

 Moreover, the amount of sugar which is passed is altogether too great 

 to be accounted for by the amount of glycogen present in the body. 

 Nor is it due to a diminished consumption of sugar by the tissues. 2 

 It has been suggested that it is caused by the absence of the glyco- 

 lytic ferment, which is described as being usually present in the blood. 

 Lepine 3 has supposed that the pancreas forms such a glycolytic ferment, 

 which effects the splitting of sugar prior to its oxidation in the tissues. 

 But Minkowski 4 has shown that the blood of an animal deprived of its 

 pancreas still possesses just as much power of glycolysis as a normal 

 animal. Kausch, 5 who succeeded in producing diabetes in ducks and 

 geese by pancreatic extirpation, also found that, after removal of the 

 liver in the diabetic animal, moderate amounts of sugar were still con- 

 sumed in the tissues. Pancreatic glycosuria diminishes or disappears 

 during fever. 6 



The symptoms are not allayed by giving raw pancreas with the 

 food, as those of thyroidectomy are by feeding with raw thyroid. Nor 



1 Cf. Hedon, Compt. rend. Acad. d. sc., Paris, 1893, tome clvi. p. 649 ; and Thiroloix, 

 Arch, de physiol. norm, etpath., Paris, 1892. 



2 Kaufmann, Compt. rend. Acad. d. sc., Paris, 1894, tome cxviii. p. 656; Arch, dephysiol. 

 norm, etpat.h., Paris, 1896, p. 151. 



3 " Le ferment glycolytique et la pathogenic du diabete," Paris, 1891. Lt'pine's theory 

 is supported by Vaughan Harley (Brit. Med. Journ., London, 27th August 1892), and 

 has been criticised by, amongst others, Spitzer (Berl. klin. Wchnschr., 1894, S. 949). 



4 Arch. f. exper. Path. u. PharmakoL, Leipzig, 1893, Bd. xxxi. 



5 Ibid., 1896, Bd. xxxvii. S. 274 ; and 1897, Bd. xxxix. S. 219. 



6 Kaufmann, Compt. rend. Soc. de biol., Paris, 1896, p. 227. Fever was found by Poore 

 to diminish sugar in natural diabetes (Trans. Clin. Soc. London, 1894). 



VOL. i. 59 



