The relation of pancreatic extract to the sugar of the blood

Abstract

In January, 1912, I reported preparation of pancreas which when injected intravenously into dogs that had been rendered diabetic by pancreatectomy, lowered both the output of sugar and the D/N ratio. This preparation seemed to offer a ready means of attack for several of the problems bearing on the relation of the pancreas to sugar metabolism. Possibly the simplest of these is the relation between the amount of sugar present in the blood and the abundance of the pancreatic hormone present, and this is a preliminary report of my work on this subject.

Cats were killed and their blood was collected. The protein was removed and the blood was decolorized by a modification of the phosphotungstic acid method reported by Oppler. In determining the amount of sugar Munson and Walker's “Uniform method of sugar determination” was used and gave consistent results. In order to test its efficiency the method was controlled by division of a sample of blood into two portions. In one of these the glucose was estimated directly. To the other a known amount of glucose was added and then this amount was subtracted from the total recovered, leaving a remainder which should equal the amount found in the portion estimated directly. The results of one such control are shown in Table I.

It was necessary next to determine the amount of sugar in the blood of normal cats. The results for a series of ten cats are given in Table 11. It will be noticed that with the exception of the cat which gave 76 mgm.–obviously an anomalous case the greatest variation from the average is 4 mgms. The starred numbers indicate controls such as are reported in Table I.