亚硒酸钠抗红细胞膜蛋白交联作用的机理探讨

A STUDY ON ANTI-CROSSLINKING MECHANISM OF Na_2SeO_3 WITH ERYTHROCYTE MEMBRANE PROTEINS

邻苯二酚氧化处理人红细胞膜会导致膜蛋白交联,产生高分子聚合物(HMP)。用N—乙基马来酰胺(NEM)封闭膜蛋白硫基,则不产生HMP。预先用Na SeO_3(0.05mol/L)处理红细胞膜,也同样不产生HMP。用N—(3-芘)马来酰胺(N-〔3-P〕NEM)标记红细胞膜来测试不同浓度Na_2SeO_3对荧光强度的影响。结果表明,随着Na SeO_3浓度增高荧光强度相应降低。Na_2SeO_3对红细胞膜的预处理时间和荧光强度的变化有关。经Na SeO_3处理的红细胞膜ESR谱提示了Na_2SeO_3与材相互作用有关。用荧光法测定膜结合硒含量表明,Na_2SeO_3处理红细胞膜可导致膜结合硒含量增高。推测,Na SeO_3很可能与膜蛋白疏基作用形成结合硒,从而起到抗膜蛋白交联作用。

superoxiae anion(O2) proaucea by pyrogamc acia, pn 8.4, inauces eryth-rocyte membrane protein crosslinking forming high molecular polymers (HMP) . No HMP is formed when erythrocyte membranes were pretreated with N-ethy-Imaleimide or 0.05 mol/L Na2SeO3.The fluorescence intensity of erythrocyte membranes labelled with N-(3-pyrenyl) maleimide decreases with increase of Na2SeO3 concentration used for pretreatment of erythrocyte membranes and is related to the time pretreated. ESR spectra of erythrocyte membranes treated with Na2SeO3 indicate the interaction of Na2SeO3 with erythrocyte membranes. The amount of Se associated with erythrocyte membranes increases obviously after treated with Na2SeO3. These results suggest that the anti-crosslinking of Na2SeO3 with erythrocyte membrane proteins maybe due to the interaction of Na2SeO3 with SH-group of protein by forming SH associated Se.