A Quantitative Study of Succinic Acid in Muscle. II

Abstract

A method is worked out for estimating malic acid in muscle, and for total succinic, fumaric and malic acids taken together. When minced muscle, suspended in buffer solution, is placed alternately under anaerobic and aerobic conditions, the succinic acid content rises in N, falls in O, rises again in N, and so on. With similarly repeated changes of atmosphere, total succinic, malic, and fumaric acids taken together rises in anaerobiosis and falls in aerobiosis. Malic acid is highest in fresh muscle (about 12-18 mgm. per 100 gm.); it falls to practically O in N, and on admission of O it may rise, but very slightly. When succinic acid disappears in O it is oxidized further than to fumaric and malic acids; and when the succinic acid maximum is renewed in N, the latter acid is formed from some other source than reversibly from fumaric and malic acids. The results also suggest that production of succinic acid is hindered by accumulation of the acid and make possible the hypothesis that in vivo production and oxidation go on continuously.