Succinate oxidation in rat liver mitochondria in vitamin E deficiency

The respiratory decline observed in vitamin E-deficient mitonchondria is not due to alterations either in the content of cytochromes or in the activity of succinate dehydrogenase. There is a decrease in the ratio of DNP-stimulated to Mg²⁺-activated ATPase of liver mitonchondria in the deficiency condition, indicative of membrane damage. Addition of lysolecithin to liver mitochondria from control rats does not affect succinoxidase activity per se, however it can alter the response of ATPase to DNP and Mg²⁺. The increased lysolecithin content of mitochondria in vitamin E-deficiency could probably cause respiratory decline indirectly through membrane damage.