Blood Lactates in Various Anoxemic States.

Abstract

In the course of an investigation on the general subject of the oxidative aspect of functional metabolism which is being carried on in this laboratory, it seemed desirable to test the validity of the hypothesis of A. V. Hill 1 that lactic acid serves as a “governor” of recovery oxidation. To this end two techniques have been developed for the production in the anesthetized dog of anoxemic states, which have been shown by Fletcher and Hopkins, 2 and others, to be the sole cause of excess tissue lactates. Throughout, dogs anesthetized by intraperitoneal injection of amytal were employed. Samples of blood for analysis were drawn from the femoral artery. The recently published method of Friedemann, Cotonio and Shaffer 3 was used for the determination of lactic acid in the blood so obtained.

Artificial Exercise. Two sheet brass electrodes were implanted in the subcutaneous tissues over the midcervical and sacral regions of the spinal cord. By means of faradic stimulation, a regular series of short, vigorous, tetanic contractions, involving the muscles of the trunk and extremities, were produced over a period of 15 minutes. During this intense muscular activity the oxygen consumption of the animal increased eight-fold. The observed changes in blood lactates are shown in Table I.