910 PHYSIOLOGY 



have seen that in the absence of carbohydrates the last stages in the 

 oxidation of fats make default so that the partially oxidised fatty 

 acids, oxybutyric acid and aceto-acetic acid, accumulate in large 

 quantities and are excreted as such or as acetone in the urine. Not 

 only does this involve a loss of energy to the body, but these organic 

 acids require other bases for their neutralisation. Up to a certain 

 point they will be excreted in the urine in combination with the fixed 

 alkalies. When these are no longer present in sufficient quantity they 

 will be excreted in combination with ammonia, so that the ammonia 

 of the urine is largely increased (v. Table III). If the condition of 

 carbohydrate starvation be continued, this mechanism of neutralisa- 

 tion is insufficient and the phenomena of acidosis, dyspnoea and coma, 

 ensue, resulting in the death of the animal. 



Another effect of continued administration of phloridzin is fat 

 infiltration of the liver. This is merely a result of the carbohydrate 

 starvation. A similar condition of fat infiltration can be brought 

 about by feeding with a pure protein plus fat diet. The liver seems to 

 be able to act as a storehouse either of fat or of carbohydrate, so that 

 there is an inverse ratio between the amount of glycogen and the 

 amount of fat stored up in the liver at any given time. It has been 

 shown that the fat in the liver under these circumstances is simply 

 fat which has been transferred to this organ from the ordinary fat 

 depots, subcutaneous tissues, &c., of the body. 



(4) PANCREATIC DIABETES. Von Mering and Minkowski found 

 that total excision of the pancreas gives rise to a severe and rapidly 

 fatal diabetes, which presents many similarities to the severer 

 cases of diabetes in man. One of the main difficulties in the 

 operation of excision of the pancreas lies in the fact that the 

 tissues of a diabetic are extremely prone to infection. It is almost 

 impossible after total excision of the pancreas, when diabetes has been ' 

 set up, to procure healing of the wounds without suppuration. The 

 operation is therefore usually carried out in two stages. In the first 

 stage one small portion of the tail of the pancreas is transplanted 

 under the skin of the abdomen, while the rest of the gland is excised. 

 Such animals do not get diabetes and therefore have a chance of 

 recovery from the severe operation. When the wounds are quite 

 healed the transplanted portion is removed through a simple skin 

 incision. The second operation is followed in a few hours by the 

 appearance of a large amount of sugar, 5 to 10 per cent, in the urine. 

 The glycosuria persists, the animal rapidly wastes, and finally dies 

 at the end of two to three weeks from diabetic coma. From the 

 nature of the operation it is evident that the condition of diabetes 

 observed under these circumstances has nothing to do with the presence 

 or absence of the pancreatic secretion from the intestine, since this 



