Abstract: | It is shown that in case of antioxidant insufficiency (AOI) activation of NADPH- and ascorbate-dependent lipid peroxidation (LPO) in sarcoplasmic reticulum (SR) of skeletal muscles proceeds 1.7 and 4.1 times faster, respectively. Activation of lipid peroxidation in AOI leads to damage of Ca2+ transport processes in SR of skeletal muscles. Under these conditions ATP-dependent accumulation of 45Ca (by 88%) and Ca(2+)-ATPase (by 14%) activity in SR of skeletal muscles falls. In case of AOI a significant disturbance of passive Ca2+ transport in SR of skeletal muscles takes place, being characterized by an increased passive 45Ca output from vesicles due to breakage of the biomembrane permeability as a result of lipid peroxidation of membranes. Treatment of animals with ionol, a synthetic antioxidant, causes a decrease of activated NADPH- and ascorbate-dependent LPO in SR of skeletal muscles and stabilization of Ca2+ transport processes. |