Polyamine and Magnesium Effects on Mitochondrial Respiration in Control and Heat-Acclimated Rats

Abstract
Studies were made of polyamine and Mg++ effects on rat liver mitochondrial α ketoglutarate oxidase (αKGO) and succinoxidase (SO). High spermidine levels suppress S3 and S4 of αKGO at 0.6–1.17 mM Mg++: some combinations of it and Mg++ increase the respiratory control ratio (RCR). Spermine suppresses S4 of αKGO and increases the RCR but suppresses the RCR of SO at high levels. In heat-acclimated (HA) animals in which we have studied only spermine effects on αKGO, RCRs of HA rats are greatly increased compared to those of controls.