The activity of the cytochrome system in muscle and its relation to myoglobin

Abstract

The activities of succinic dehydrogenase, succinic oxidase and cytochrome oxidase were detd. in enzyme prepns. from a variety of muscles: the effects of age, type of muscle and spp., were considered. In prepns. from heart, longissimus dorsi, diaphragm and psoas muscles of the horse the 3 enzymic activities increased rapidly up to the age of 2 yrs. and thereafter were constant. In the adult animal the order of increasing enzymic activity was given by. longissimus dorsi, psoas, diaphragm and heart. In fetal horse heart the activity of cytochrome oxidase was appreciable when that of succinic dehydrogenase and succinic oxidase system was very low. In prepns. having relatively high cytochrome oxidase activity, (e.g. horse heart), the activities of succinic dehydrogenase and of succinic oxidase were greater than those with low cytochrome oxidase activity. A large quantity of gel material of low enzymic activity, was always obtained during the prepns. of enzyme suspensions from pigeon-breast muscle. A significant correlation was found between the percentage of myoglobin and the activity of the corresponding enzyme prepn.