Abstract
The following report deals with the blood sugar curve after the intravenous injection of insulin into normal and depancreatized dogs. The study includes over 50 observations upon normal and 350 observations upon diabetic animals.
Experiments on blood sugar lowering were performed on male dogs weighing 12 to 18 kilos, 18 hours after the last (afternoon) feeding and routine insulin injection. Doses from .02 to 1.0 units of insulin (Lilly) per kilo given in a volume of 1 cc. were injected into the jugular vein. Glucose determinations on tungstic acid filtrates were made by the Shaffer-Hartman method. The time intervals shown in the chart were found to bring out most clearly the differences in the 2 types of curves.
The chart gives typical examples of time curves after the injection of 0.1 unit of insulin per kilo intravenously before and after removal of the pancreas. The upper curves show the results expressed in mg. % of blood sugar. The striking change in amount of sugar transported from blood to tissues by a given dose of insulin is apparent. The conclusion that in the diabetic the activity of insulin is enhanced is shown to be erroneous when we compare relative blood sugar lowering on the basis of the fraction removed, assigning the value of 100% to each initial blood sugar level (Scott 1 ). This is shown in the lower set of curves.
In the normal dog the blood sugar falls rapidly, reaching its lowest level within 20 to 30 minutes after the injection of insulin. This is followed by an abrupt rise and then restoration to approximately the original value within 90 minutes. The return phase is usually represented by a broken curve frequently giving several maxima and minima.
Get full access to this article
View all access options for this article.