Open AccessEffect of Irradiation in vitro on Mitochondrial Metabolism
Author(s) -
Clark J. B.
Publication year - 1967
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1967.tb00099.x
Subject(s) - oxidizing agent , mitochondrion , glutamate receptor , citric acid cycle , irradiation , respiration , biochemistry , in vitro , chemistry , isocitrate dehydrogenase , citric acid , metabolism , biology , organic chemistry , anatomy , enzyme , physics , receptor , nuclear physics
1 The ability of rat liver mitochondria to oxidise β‐hydroxybutyrate, succinate, α‐oxoglutarate, pyruvate, glutamate and isocitrate has been studied after irradiating the mitochondria in vitro with radiation doses within the range 0–100 krads. 2 The P/O (P/2e) ratio and the respiratory control, as well as the various mitochondrial respiratory states, have been examined by use of the oxygen electrode. 3 The P/O ratios of mitochondria oxidizing β‐hydroxybutyrate and succinate fell by 10% after a 100 krads dose of irradiation; after the same dose the P/O ratio with glutamate or pyruvate fell by 20% with α‐oxoglutarate 25% and with isocitrate 30%. 4 In all cases except isocitrate, the respiratory control fell more dramatically than the P/O ratio after irradiation. After 100 krads dose of irradiation the respiratory control of mitochondria oxidizing succinate fell by 20%; isocitrate by 30%; pyruvate or glutamate by 34%; β‐hydroxybutyrate by 37% and α‐oxoglutarate by 42%. 5 The results are discussed with respect to the normal control of mitochondrial citric acid cycle oxidations, the role that the structural integrity of the mitochondrion plays therein and the effects of irradiation on cellular systems in general.