草酸钙晶体表面结合蛋白质的研究

Urinary calcium oxalate crystal surface binding proteins in normal subjects and calcium oxalate stone formers

目的 :了解草酸钙晶体表面结合蛋白质在结石形成过程中的作用。方法 :用草酸钙过饱和结晶法制备正常人和草酸钙结石患者尿草酸钙晶体表面结合物质 ( CSBS) ,经 DEAE- SepharoseCL- 6B柱层析分离蛋白质和葡胺聚糖 ,用 SDS-聚丙烯酰胺凝胶电泳 ( SDS- PAGE)测定蛋白质组成和分子量 ,用氨基酸自动分析仪测定蛋白质的氨基酸组成。结果 :正常人 CSBS中主要含分子量为310 0 0的尿凝血酶原激活肽片段 1( UPTF1)和分子量为 670 0 0的白蛋白。结石患者 CSBS以白蛋白为主 ,其 UPTF1含量低于正常人。结论 :正常人和结石患者晶体表面结合蛋白质组成的差异可能与结石形成有关。

Purpose: To compare urinary calcium oxalate crystal surface binding proteins in normal subjects and calcium oxalate stone formers. Methods: Urinary calcium oxalate crystal surface binding substances (CSBS) of normal subjects and calcium oxalate stone formers were produced by calcium oxalate supersaturation crystallization. The proteins and glycosaminoglycans (GAGs) were separated by a DEAE-Sepharose CL-6B chromatogrophy. The composition and molecular weight of proteins were determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The amino acid constituents were also analyzed. Results: The results showed that the normal subject′s CSBS consisted of urinary prothrombin fragment 1 (UPTF 1) with a molecular weight of 31 000 and albumin with a molecular weight of 67 000. In the calcium oxalate stone formers, albumin was the predominant component, UPTF 1 was significantly less than that in normal subjects. Conclusions: It was concluded that the difference of composition of crystal surface binding proteins between normal subjects and stone formers might be related to the tendency of stone formation in stone formers.