

THE PANCREAS AND THE LIVER 123 



its way into the blood and then into the urine. An 

 attractive hypothesis of this type claims that there 

 really are two opposing forces that work in the 

 normal man, an accelerating force, due to the hor- 

 mone from the adrenal glands, which accelerates 

 the conversion of glycogen into glucose, and a re- 

 tarding force, due to the pancreatic hormone, which 

 tends to slow up and regulate such a reaction. To 

 support this hypothesis, Dr. Zuelzer, its author, de- 

 scribes an experiment with a dog that had had its 

 pancreas removed and its adrenal veins ligated. 

 No diabetes followed. 



We may represent what happens as follows: 



carbohydrates > stored in liver as glycogen > 



given out as glucose. The blood, when analyzed is 

 always found to contain a small amount of glucose. 

 Under normal conditions that glucose is fairly con- 

 stant in amount, ranging from 0.07 to 0.1 per cent. 

 Even in a starving animal the blood sugar is found 

 to remain constant. This makes us believe that 

 under such conditions, with all carbohydrate vir- 

 tually absent from the body, part of the fat mole- 

 cule, and perhaps part of the protein molecule, is 

 converted into sugar. Only in pathological cases, 

 such as are met with in diabetes, does the amount 

 of blood sugar materially increase. 



Now the question arises, by what mechanism is 

 the blood sugar of the normal human being kept 

 constant? Why despite the varying quantity of 



