Myothermic Studies On the Muscle Poisoned with Monoiodoacetic Acid.

1. The magnitude of the initial heat production in relation to the maximum tension developed and its time-distribution is entirely unaffected through poisoning with monoiodoacetic acid. 2. The ratio of the area of tension-time curve to the maximum tension developed, i. e. the equivalent duration of single twitch, is not affected through poisoning with monoiodoacetic acid. 3. A considerable amount of the recovery heat production takes place in the poisoned muscle under aerobic conditions, though it is less in degree than that of the normal one, and sometimes it fails entirely, as in the normal muscle under anaerobic conditions. 4. The delayed anaerobic heat production of the poisoned muscle occurs in the same degree as in that of a normal muscle. 5. From the results obtained in this investigation, some considerations were made with referrence to the chemical processes played in muscular contraction. Finally, our sincere thanks are due to Prof. Oinuma for his suggestions and advice during our experiments.