Relation of Blood Sugar to Glycosuria. 



69 



plus an excess. 1 By comparing the urinary output of sugar in a 

 given period of time with the "excess" of sugar present in the 

 blood, a definite mathematical relation is found to exist between 

 the percentage of sugar in the urine, and that in the blood. The 

 proportion between the two tends to approach a constant, in one 

 and the same individual, on a given day. This applies to individ- 

 uals with normally functionating kidneys. In those with de- 

 fective kidneys there is no parallelism. The hyperglycemia in 

 such individuals is usually greater in proportion to the glycosuria 

 than it is in those with normally functionating kidneys. 



Diuresis in diabetes mellitus plays an important role in de- 

 termining the total amount of sugar eliminated in the urine, but 

 has no influence on its concentration or percentage. 



41 (1105) 



The relation of the sugar content and concentration of the blood 

 to urine formation. (Preliminary report.) 



By E. M. Ewing. 



[From the Laboratory of Physiology, University and Bellevue Hospital 



Medical College.] 



The present experiments were performed in an effort to estab- 

 lish a standard of comparison for further experiments involving 

 the study of the fate of sugar injected into the circulatory system 

 under various conditions. 



Various amounts of a dextrose solution (40 gm. in 40 c.c. 

 water) were injected into the femoral veins of dogs under local 

 anesthesia, and 20 c.c. of blood drawn from the femoral artery at 

 15-minute intervals. Twenty c.c. of citrated dog's blood pre- 

 viously prepared were injected into the artery immediately after- 

 ward, thus maintaining the normal concentration of the blood as 

 indicated by the specific gravity and hemoglobin percentage. 

 The specific gravity, hemoglobin and sugar content of the blood 

 were determined, and also the urine obtained by catheter was 



1 The largest amount of sugar which may be present in the blood (with constant 

 blood volume conditions) without giving rise to a glycosuria, is estimated at o.i 

 per cent. In determining the excess of sugar in the blood, o.i per cent, is deducted 

 from the values of blood sugar obtained after correction for blood volume. 



