86 LECTURE V. 



gland may be removed, and, in fact, that portion directly connected 

 with the intestine, and glucosuria does not take place as long as a small 

 part of the tissue of the gland still remains in the body. A further proof 

 that pancreatic-glucosuria is not intimately connected with digestion is 

 shown by the fact that in the case of total extirpation of the gland, sugar 

 still appears in the urine after prolonged starvation, i.e., after the stomach 

 and intestines have become empty. Furthermore, it is not possible to 

 influence the existing glucosuria by feeding the gland to the animal. It is 

 interesting that after a partial elimination of the pancreas the assimilation 

 limit for sugar is considerably decreased. This is shown by the fact that 

 an animal experimented upon which did not show glucosuria would 

 eliminate sugar in the urine when the amount of carbohydrates fed to it 

 was increased, especially if the food contained glucose. 



It is particularly significant that a small piece of the gland tissue 

 usually suffices to keep the entire metabolism of carbohydrates in nor- 

 mal paths. This was shown very strikingly by the experiments of 

 Minkowski, which proved conclusively that it was not the severe operation 

 itself, but the total removal of the pancreas function, that caused the 

 great disturbance in the metabolism of carbohydrates. In dogs the lowest 

 part of the descending branch of the pancreas does not grow together with^ 

 the duodenum, but lies free in the mesentery. Minkowski separated 

 this piece from the remaining tissue of the pancreas so that it was still in 

 connection with the mesentery and without disturbing its supply of blood 

 and lymph vessels. This piece of pancreas was then drawn out through 

 the abdominal cavity, grafted under the skin, and allowed to heal to- 

 gether with the wound. After the animal had survived this operation, 

 the abdomen was again opened, and all of the rest of the pancreas removed 

 from the body. Thus only the small portion of the gland which had been 

 transplanted under the skin remained in the animal, and yet glucosuria did 

 not ensue. If, however, this part of the pancreas was finally removed, 

 sugar appeared in the urine at once. 



The fact that, in many cases, a small portion of the pancreas left in the 

 body serves to prevent the appearance of glucohemia, suggests to us 

 other possibilities. It is perfectly conceivable that the pancreatic gland 

 serves, like the liver, for example, to neutralize injurious substances, and 

 especially those which interfere with the metabolism of carbohydrates. 

 When the pancreas is removed, these products perhaps pass unhindered 

 into the circulation, and prevent the normal breaking down of sugar. If 

 this view were correct, it would follow that the injection of the blood from 

 an animal suffering from glucosuria into the circulation of a healthy 

 animal would inevitably produce the same disease. That this is not the 

 case was shown by the direct experiments of Minkowski and von Mering. 



The only remaining explanation of pancreatic-glucosuria would seem to 



