METABOLISM 87 



secretion (the "pancreatic juice," with its various 

 digestive enzymes), have been shown by experiment 

 to develop important internal secretions as well. 

 Thus it has been found that total extirpation of 

 the pancreas produces the unexpected result of 

 inaugurating glycosuria (diabetes), a condition 

 in which the kidneys constantly eliminate sugar 

 from the blood. If, however, only a small portion 

 of pancreatic tissue be left, no diabetes or only a 

 very mild form results. It is evident that the exist- 

 ence of this sort of diabetes is dependent upon the 

 absence of pancreatic tissue. Even when the pan- 

 creas has been removed, if a small part be grafted 

 in where the blood can come in contact with it, no 

 diabetes follows, a result that indicates not only 

 that the ordinary intestinal secretion has nothing to 

 do with it, but also that it is necessary for the blood 

 to flow in contact with the pancreatic tissue. For 

 this and other reasons, it has been concluded that 

 the pancreas supplies to the circulating blood an 

 important internal secretion, which, in some way 

 at present unknown, controls the utilization of sugar 

 in the animal organism, and in the absence of 

 which this sugar passes out of the body unchanged. 

 The adrenals, ductless glands attached to the 

 kidneys, have been shown, in much the same way, 

 to produce a substance, the presence of which in 

 the blood rapidly increases the blood pressure and 

 produces a strong contraction of the peripheral 

 blood-vessels. This substance has recently been 

 isolated from the extract of the gland, and is found 



