Sect. V, 1922 [39] Trans. R.S.C. 



VI. The Effect of Insulin on the Percentage Amounts of Fat and Glycogen 

 in the Liver and Other Organs of Diabetic Animals 



By F. G. Banting, M.B., C. H. Best, M.A., J. B. Collip, Ph.D., 

 J. J. R. MACLEOD, M.B., Ch.B., F.R.S.C. and E. C. Noble, M.A. 



(Read May Meeting, 1922) 



I. Glycogen in the Liver, Heart and Muscles 



(a) Liver. — Minkowski found that after total extirpation of the 

 pancreas in dogs, the percentage of glycogen in the liver fell to 0.5 

 or less even when large quantities of dextrose had been ingested. 

 When laevulose was given (in three cases) considerably larger amounts 

 of glycogen were deposited (0.72 to 8.14). Several investigators have 

 confirmed these observations except that Cruickshank has found 

 that laevulose also does not form glycogen provided the extirpation 

 of the pancreas is complete. He infers that Minkowski's results 

 with laevulose were due to the fact that all pancreatic tissue had not 

 been removed. 



In two depancreated dogs which were given large quantities of 

 cane sugar for several days preceding death we found in the liver 

 0.044-0.047 per cent, in the one, and 1.29-1.35 per cent, of glycogen 

 in the other. 



Very different results were obtained when insulin, as well as 

 sugar, was given to depancreated dogs for a few days before the 

 animal was killed. Thus, in one animal (Jan. 3rd) 13.27 per cent., 

 in another (Feb. 21st) 12.58 per cent, and in a third (March 28th) 11. 

 4 per cent, of glycogen were found in the liver. These striking differ- 

 ences indicate that one effect of insulin is to stimulate the glycogenetic 

 function of the liver and this fact, coupled with the knowledge that 

 it also raises the respiratory quotient in an hour or two after it is 

 given subcutaneously, lends support to the hypothesis that carbo- 

 hydrate can be utilized in the body only after it has been converted 

 into glycogen. 



In two other cases less striking results were obtained, namely, 

 2.85 per cent, in one (Jan. 14th) and 4.9 per cent, in another (April 2). 

 In one animal that took sucrose very greedily and to whom large 

 doses of insulin were given during the two days preceding death 

 considerably more than 12 per cent, of glycogen was found in the liver. 



(b) Heart and Muscles. — Cruickshank found that the glycogen 

 in the hearts of 6 normal dogs averaged 0.5 per cent, the maximum 



