Abstract: The stabilizing effect of trace amount of selenium on erythrocyte membranes was studied by means of spin-labeing technique in this paper. The evidences showed that, compared with in selenium-free medium, the ratio of weak immobilizing components of the labeed erythrocyte membrane proteins to that of strong ones (W/S) decreased and flexibility coefficient (F) increased by addition of selenium and incubation at 4℃ for a period of time, which suggested that the tetramers and oligomers of spectrins increased. The mild denaturing experiment by using Triton X-100 at 0℃ for one hour indicated that the selenium have inffunce on the proteins of erythrocyte membranes. The stabilization are neither due to electric interaction nor due to covanlently cross-linking. The configuration variation and subsequent transformation of dimers of spectrins to tetramers and oligomers is probably the main process leading to protection of the membrane skeletons from decomposition. More

Key words: Selenium, Skeleton, Erythrocytc membranes, Spin-labeing, ESR