[The sensitivity of catalytic subunit isoforms of Na+,K+-ATPase of rat brain to peroxide membrane modification].

The comparative study of the sensitivity of Na+, K(+)-ATPase isozymes from cerebral cortex to ascorbate-dependent membrane peroxidation was conducted. With highly inactivated Na+, K(+)-ATPase the degree of inactivation of the SH-dependent ouabain-sensitive forms alpha+ (alpha 2 and alpha 3) is higher than glycoside-resistant isoform alpha 1. The process is accompanied by simultaneous lipid peroxidation and decrease of SH-groups amount in enzyme preparations. The combined nature of the oxidative Na+, K(+)-ATPase inactivation, accompanied by the direct oxidation of enzyme SH-groups and modification of lipid environment is supposed.