806 PHYSIOLOGY 



tion is especially marked if the heart be made to work excessively by 

 raising the arterial resistance and administering adrenalin ; but taken as 

 a whole the power of utilising glucose is very inferior to that possessed 

 by normal animals. One of the most striking features of the condition 

 caused by total extirpation of the pancreas is the rapid diminution of the 

 fat depots of the body, attended by a marked condition of lipaemia and 

 accumulation of fat in the liver. The blood is so full of fat globules that 

 it has been compared in appearance to strawberries and cream. One of 

 the first effects of extirpation of the pancreas is therefore a rapid fat 

 mobilisation, and the respiratory quotient agrees with that obtained when 

 the metabolic needs of the body are being mainly satisfied at the expense 

 of the fat. The sugar of the urine, after the depletion of the glycogen 

 store of the liver, is derived from the protein, and the protein tissues of 

 the body therefore diminish as rapidly as the fat stores. On the theory 

 of deficient utilisation, it is thought that these tissues suffer from carbo- 

 hydrate starvation, even though they are bathed in a medium containing 

 an increased amount of sugar, and that the liver in response to some call 

 from the tissues turns first its glycogen and later on the proteins of the 

 body into sugar to supply this lack all to no purpose however, since the 

 tissues are unable to avail themselves of the sugar or ferment. 



According to the second view, the primary disorder affects only the 

 liver. This organ is freed from some restraining influence on its power of 

 manufacturing sugar from glycogen and from protein, so that the blood is 

 flooded with sugar, which is therefore excreted in the urine. Any deficient 

 utilisation of the sugar would be regarded as secondary to a poisoning of 

 the tissues by this overloading of their nutrient fluids with sugar. It is 

 certain that the sugar production in diabetes is excessive, as is shown by 

 the rapid wasting of the protein tissues to give rise to the sugar, and that 

 this over-production takes place in the liver is shown by the fact that 

 extirpation of the liver in the diabetic animal causes a rapid disappearance 

 of the sugar from the blood. 



According to the Vienna school (Rudinger, Falta, and others), a close 

 interaction exists between the thyroid, the suprarenals, the pancreas, and 

 the liver, the thyroid to a slight extent, the pancreas still more, inhibiting 

 the glycogenic functions of the liver, while the suprarenals through their 

 excretion of adrenalin stimulate this function. Glycsemia and glycosuria 

 caused by extirpation of the pancreas would therefore be ascribed to an 

 unchecked activity of the suprarenals. An important difference however 

 seems to exist between the two conditions. Adrenalin glycosuria comes 

 to an end when the glycogen store of the liver is exhausted, whereas pan- 

 creatic diabetes continues until the death of the animal, long after all 

 traces of glycogen have disappeared from the liver. We do not yet know 

 how the pancreas affects sugar production or utilisation in the normal 

 animal. It is generally assumed that it secretes into the blood stream a 

 hormone which may, according to the view of the nature of diabetes which 

 we adopt, pass to the tissues and enable them to utilise sugar, or pass to 



