Glycolysis in the Blood of the Goat. ∗

Abstract

A previous communication 6 reported that the normal blood sugar of the goat ranges from 24 to 65 mg. per 100 cc., levels considerably lower than those reported for other laboratory animals. A second difference between the blood of the goat and that of other animals is indicated by the data given below, namely, a difference in the behavior of the inorganic phosphate during glycolysis.

It has been repeatedly observed 2 , 7 , 10 , 15 that the fall in blood sugar which occurs in shed blood is accompanied by typical changes in the level of the inorganic phosphate. During the first few hours of glycolysis, while the sugar is being destroyed rapidly, the inorganic phosphate decreases. When the sugar has practically all disappeared and glycolysis has, perforce, either stopped or slowed to a very low rate, there is a rapid and extensive increase in the level of the inorganic phosphate. These changes during glycolysis have been observed in the blood of the dog, the rabbit and the human.

Data are given below on the changes in sugar, lactic acid, and inorganic phosphate which occur in the blood of the goat, when defibrinated and incubated at body temperature. The blood of dogs was used for control purposes.

For these studies, 75 to 100 cc. of blood was drawn from the jugular vein and defibrinated with a glass rod. Samples were withdrawn immediately for the determination of sugar, lactic acid, and inorganic phosphate. The flask containing the remainder of the blood was stoppered and placed in the incubator at a temperature of 37° to 38°C. Aseptic precautions were not taken as it has been shown that slight bacterial contamination alters neither the glycolytic rate 8 , 13 nor the course of the accompanying changes in the inorganic phosphate. 10 Samples were withdrawn for the determinations at intervals of 1 to 4 hours, and the experiments were continued for 12 to 24 hours.