THE EFFECTS OF CAFFEINE AND THEOBROMINE DERIVATIVES ON MUSCLE GLYCOLYSIS1’2

In a former paper (Gemmill, 1) the effect of caffeine and theobromine deriva-tives on oxygen consumption of the isolated rat’s diaphragm was described. It was found that caffeine and numerous theobromine derivatives with substitutions in the 1 position stimulated the respiratory metabolism of the isolated muscle preparation. It was impossible to tell from these experiments whether or not the stimulation was a non-specific one resulting from contracture of the muscle or whether it was specific from stimulation of some definite part of the metabolic process occurring in muscle. Therefore it was decided to extend this study by testing the effects of the same group of substances on glycolysis and to make an intensive study of caffeine on this mechanism. There have been a few reports on the effect of caffeine on glycolysis and these reports concern only work on intact muscle. Meyerhof (2) states that the addi-tion of caffeine increases the lactate formation of muscle. This work was con-tinued and reported in detail by Matsuoka (3). David (4) also has shown a large change in lactate in caffeine contracture. Hill (5) demonstrated that afte