120 GLANDS IN HEALTH AND DISEASE 



the external secretion, produces the bile, which 

 flows to the exterior ; the second, the internal secre- 

 tion, forms sugar which immediately enters into 

 the blood of the general circulation." 



Claude Bernard, in fact, coined the phrase "in- 

 ternal secretion," though his views as to the influ- 

 ence of this secretion on the rest of the body, if 

 not vague, were misleading. 



The pancreas and its internal secretion. It is 

 now time to turn to Minkowski and von Mering's 

 experiments which proved that the pancreas regu- 

 lates the sugar metabolism by means of a hormone 

 which it develops. These investigators found that 

 by carefully and completely extirpating the pan- 

 creas in a dog, the animal develops diabetes. Such 

 an operation was invariably followed by the death 

 of the animal within a few weeks, but during those 

 weeks it suffered severely from the sugar disease. 



Diabetes, as you may know, is the unfortu- 

 nately all too common disease wherein the body 

 cannot use or "burn" all the sugar that it gets, with 

 the result that we find it present in excessive quan- 

 tity in the blood (hyperglycemia), and sooner or 

 later an excessive quantity of sugar appears in the 

 urine (glycosuria). Since the liver is the central 

 organ for sugar metabolism, we must look for a dis- 

 turbance in the liver function. The German in- 

 vestigators showed that such a disturbance occurs 

 when the pancreas is cut out of the system. 



