IT is well known that the rate of lactic acid formation in surviving
muscle is accelerated when the muscle is placed in fluids of alkaline
reaction, and retarded by acids. It is also known that the lactic acid
content of the blood is influenced, among other things, by the H-ion
concentration of the blood itself. Thus Macleod and Knapp [1918]
showed that after administration of alkali the blood lactic acid was increased. Anrep and Cannan [1923] demonstrated that the lactic acid
content of the blood circulating in the heart-lung preparation could be
caused to rise and fall with the pH of the circulating blood.