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THE METABOLISM OF CARBOHYDRATES 849 



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 extir- 

 pation 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 carbohydrate 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 proved by the fact that 

 extirpation of this organ in the diabetic animal causes a rapid disappear- 

 ance of the sugar from the blood. 



According to the Vienna school (Rudinger, Fait a, 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 the liver and inhibit 

 e sugar production in this organ. A very small portion of the pancreas 

 sufficient for this purpose, but we have been unable to imitate the action 

 of the pancreas still in vascular connection with the body by injection or 

 administration of extracts cf this organ. Even conneption of a healthy 

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