CHAPTEK XXII 



DIABETES 



As with gout, diabetes has been the subject of such an 

 enormous amount of discussion and experimentation that it is 

 impossible in this place to attempt to review the entire history 

 and literature of the subject, which has already been thoroughly 

 done by a number of physiological chemists and clinicians in 

 the places cited below. 1 In this chapter will be given as 

 briefly as possible merely an epitome of the views now held by 

 the best authorities concerning diabetes, and the problems of 

 carbohydrate metabolism in as far as they relate to diabetes. 



Diabetes is usually distinguished from transient forms of 

 glycosuria, although it is well understood that no sharp line 

 between many conditions of transient glycosuria and chronic 

 glycosuria, or diabetes, can always be drawn. In diabetes the 

 sugar present in the urine is predominantly dextrose, small 

 quantities of levulose and other sugars frequently accompany- 

 ing it. There exist cases, however, in which the urine contains 

 for a long period of time other sugars, particularly levulose 

 and pentose, but these cases are not associated with the pro- 

 found systemic disturbances of diabetes, presumably because 

 these sugars are not of such great importance for the nutrition 

 of the body as is dextrose. 



Glycosuria may be produced by many different causes, which 

 may be grouped under the following heads : (1) alimentary ;, 

 (2) nervous; (3) drugs and other chemicals; (4) pancreatic. 



I. ALIMENTARY GLYCOSURIA 



Under ordinary conditions the sugars taken with the food,, 

 or formed from the carbohydrates of the food, are in large part 

 converted into glycogen, and temporarily stored in this form. 

 The arterial blood contains quite constantly a small amount of 



'Pfliiger, Pfliiger's Arch., 1903 (96), 1 ; v. Noorden, "Die Zuckerkrank- 

 heit und ihre Behandlung" ; also translation of his Herter lectures, entitled, 

 "Diabetes Mellitus," New York, ]905, (without bibliography); Macleod, 

 pp. 312-386, in "Kecent Advances in Physiology and Biochemistry," London, 

 1906; Abderhalden, " Lehrbuch der physiologischen Chemie," Berlin, 1906, 

 pp. 13-108. Eeferences will generally be cited only when not contained in the 

 above reviews. 



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