哇巴因结合肽拮抗哇巴因抑制钠泵作用的研究

The antagnoist action of ouabain conjugated peptide for ouabains inhibition on Na^+,K ~ +-ATPase

目的 获得特异性的哇巴因结合肽 (OCP) ,拮抗或阻断哇巴因 (EO)对Na+ 、K+ ATP酶的抑制作用 ,为高血压的治疗提供理论和实验依据。方法 采用生物淘洗的方法 ,筛选噬菌体展示 12肽库。随机挑选所筛出的结合肽 ,经扩增、DNA提取及测序 ,获得其基因序列 ,然后推导出其氨基酸序列。选择序列一致率最高的肽序列 ,进行肽合成。采用红细胞86Rb摄取率实验测定OCP拮抗EO对Na+ 、K+ ATP酶的抑制作用。结果 Leu Leu Ala Asp Thr Thr His His Arg Pro Trp Thr为筛选肽序列一致率最高的肽序列。红细胞86Rb摄取实验结果表明 ,OCP可以阻断EO对红细胞膜钠泵的抑制作用 ,可以使红细胞摄86Rb率从 6 0 %升高到 80 %左右 ,呈现一定的剂量依赖关系。结论 本实验结果不仅获得了特异性OCP ,而且为高血压的治疗以及与EO相关疾病的诊断、治疗提供了一条新的途径。

Objective To obtain ouabain conjugated peptides (OCP) for blockage or antagonist actions of endogenous ouabain (EO) on sodium pump, so as to provide theoretical and experimental bases for hypertension therapy. Methods We screened the phage and displayed 12-peptide library by biopanning for OCP. The DNA sequences of each selected peptide were determined and the amino acid sequences were deduced. We selected the highest consistence of the polypeptide, which was synthesized by peptide synthesizer. Bioactivity of OCP was measured by erythrocyte 86Rb uptake. Results Leu-Leu-Ala-Asp-Thr-Thr-His-His-Arg-Pro-Trp-Thr had the highest consistence of peptide sequence, which was the sequence of synthetic peptide. The result of erythrocyte 86Rb uptake verified that OCP was capable of suppressing the inhibitiory action between ouabain and sodium pump on the surface of erythrocyte, which improved the erythrocyte 86Rb uptake from 60% to 80%. The result showed that the efficiency was in a dose-dependent manner. Conclusion The results not only obtain distinctive OCP, but also supply a valuable way in treatment of hypertension as well as diagnosis and therapy of EO-related diseases.