The antidiabetic functions of the pancreas and the successful isolation of the antidiabetic hormone - insulin / by J.J.R. Macleod and F.G. Banting.

  • Macleod, J. J. R. (John James Rickard), 1876-1935
Date:
1923 [©1924]
Catalogue details

Licence: Public Domain Mark

Credit: The antidiabetic functions of the pancreas and the successful isolation of the antidiabetic hormone - insulin / by J.J.R. Macleod and F.G. Banting. Source: Wellcome Collection.

    60/86 (page 50)
    and Smith's experiments would seem to show, by its activating an enzyme which has this effect. After the insulin effect has begun to wear off, perhaps because of its destruction or because of its excretion, the blood sugar begins to recover and the rate of re¬ covery is in general largely in proportion to the amount of available glycogen in the liver. When there is little glycogen in the liver, as in starved animals, the recovery is relatively slow, whereas in animals that have been liberally fed with carbohydrate up to the time insulin was given, recovery is much more rapid. That recovery depends largely upon the glycogen stored in the body, has a practical application in the administration of in¬ sulin to man. It is obviously far safer to give insulin to patients who have already a good store of glycogen in the body, than to those that are glycogen-free. It is no doubt on this account that a dose of insulin that is quite safe for a well-fed rabbit will cause hypoglycemia in a depancreatisecl dog of many times the body-weight of the rabbit. In 'practice, therefore, you will have to be most careful to see that symptoms do not develop in patients who are given insidin for the first time; later on, when the glycogen stores have become fairly ade¬ quate, the dangers are likely to be less. These important relationships of insulin to the glyco¬ gen stores of the animals have been shown in a slightly different way, namely, by observing the blood sugar of animals investigated in pairs, one animal in each case having a large store of glycogen in the body, and the other a very small one. When both animals of each pair were given exactly the same amounts of insulin, there was a striking difference in the results. In the case of the starved animal in the first pair, convulsions developed in less than two hours, while in the fed animal it took three hours for them to develop. The blood sugar came down to practically the same level in both cases, but