Succinic and Cytochrome Oxidase Activity of Rat Liver Mitochondria After in Vitro Irradiation With Ultraviolet Light

Abstract

Five per cent suspensions of rat liver mitochondria were irradiated with ultraviolet light for varying periods of time and the succinoxidase and cytochrome oxidase activity were determined. Both succinoxidase and cytochrome oxidase activity were reduced by irradiation with ultraviolet. The order of magnitude of the ultraviolet energy necessary to produce such changes is much less than that necessary to produce chemical changes in nucleic acid derivatives, and approaches the amount which has been shown to produce lethal and other biological effects.