INTEENAL EESTITUTIVE SECEETIONS 



315 



and glycosuria which represent the main symptoms of diabetes 

 depend on a lowered glycolysis, i.e. on the fact that the diabetic 

 organism does not possess the normal capacity for splitting up the 

 sugar as it is formed. This capacity is not entirely lost, but it is 

 much diminished. Kiilz, indeed, noted that in severe cases of 

 diabetes the amount of sugar in the urine is always lower than 

 the total of carbohydrates ingested, and absorbed from the intestine 

 in the form of sugar. 



Another very important observation of Klilz is that diabetics 

 are capable of breaking up laevulose or fruit sugar, which turns 





FIG. 99. Hepatic cells of man under normal conditions (A), and in a diabetic subject (B) treated 

 with gum iodide. (Frerichs.) At A the colour is strongly reddish-brown from the glycogen 

 present ; at B the colour is pale, from small amount of glycogen. 



the plane of polarised light to the left. They can also use inulin, 

 which is converted into laevulose as starch is converted into 

 dextrose. Lastly, he observed that saccharose (which splits half 

 into laevulose and half into dextrose), when given in severe cases 

 of diabetes, increased the sugar in the urine by about half the 

 amount of sugar (in the form of dextrose) administered as 

 saccharose. The repetition of this experiment by several other 

 observers yielded results which were not always in agreement 

 with those of Kiilz. This proves that different diabetics behave 

 differently. Generally speaking, however, the ingested laevulose 

 either does not appear or appears only in very small quantities in 

 the urine. Sometimes part of the laevulose is converted into 

 dextrose, and appears as such in the urine. On the strength of 



