Nicotinamide, cozymase and tissue metabolism

DURING the course of experiments on the respiratory activities of intact, minced and ground mammalian tissues we have found that there exists in brain and in liver a very active mechanism which accomplishes the breakdown of cozymase u'nder both aerobic and anaerobic conditions. We have also found that this mechanism can be inhibited in a specific manner by nicotinamide. A preliminary note incorporating these results has already been published [Mann & Quastel, 1941]. The following communication is concerned with a description in detail of these atid further results, together with observations on the effects of nico- tinamide on the inhibitory activity of cobra venom in respiratory systems.