Oxidative phosphorylation in the livers of normal and malnourished human infants

Abstract

1. Respiration, oxidative phosphorylation and the uptake of phosphate into phosphatidic acid have been measured in samples of liver obtained by biopsy from malnourished and recovered human infants. All measurements were made on homogenates. 2. Respiration was well maintained in the malnourished liver, but phosphorylation was slightly reduced, and P uptake into phosphatidic acid greatly reduced. Ageing by preincubation caused a much greater reduction of phosphorylation in homogenates from malnourished than from normal livers. Albumin had some protective effect. 3. In the malnourished infants the livers were usually fatty. All the changes observed were more severe in the more fatty livers. 4. Homogenates from malnourished fatty livers were capable of inhibiting phosphorylation by normal rat liver mitochondria. This and other evidence suggests that the reduction in phosphorylation in the malnourished livers may result from the uncoupling action of free fatty acids or some other lipid derivative. 5. The question is discussed whether there may be changes of mitochondrial function in the malnourished livers, independent of fatty infiltration.