【摘要】 目的　探讨人血清中淀粉样蛋白P(SAP)与血浆脂蛋白中HDL、VLDL和LDL相互作用机制。方法　①Sepharose 4B(Pharmacia)亲和层析法提取人血清SAP ,DEAE Sepharose层析纯化。SDS 聚丙烯酰胺凝胶电泳与标准SAP(Sigma)检测。采用免疫探针生物素化试剂盒 (Sigma)以 1∶10比例接合于生物素氨基己酸 N 羟基 硫琥珀酰亚胺酯。得到生物素 SAP。②VLDL、LDL、HDL用超速离心法分离。③以TMBZ底物试剂盒用固相平板测定法检测SAP与脂蛋白相互结合。结果　①生理条件的Ca2 +浓度下 ,生物素 SAP以剂量依赖方式选择性地与HDL、VLDL结合。当SAP浓度分别达到 1.5nM和 2nM时 ,SAP与HDL、VLDL的结合达到半饱和 ,当SAP浓度达到 4nM和 16nM时 ,SAP与HDL、VLDL结合达到饱和。②SAP与HDL和VLDL的结合具有Ca2 +依赖性。③EDTA可影响SAP和HDL、VLDL结合。④无论有无Ca2 +和EDTA存在 ,未发现SAP和LDL间的结合。结论　SAP与HDL和VLDL结合而不与LDL结合。更多还原

【Abstract】 Objective: To study the interation between human SAP and serum high density lipoprotein (HDL), low density lipoprotein (ldl) and very low density lipioprotein (VLDL). Methods: Serum amyloid P component (SAP) is a glycoprotein in human plasma. It is previously shown that SAP is specifically localized in human atherosclerotic lesions, suggesting that SAP may play a role in atherogenesis. In this study, the interactions between human SAP and high density lipoprotein (HDL), low density lipoprotein (LDL) and very low density lipoprotein (VLDL) were investigated by using a solid phase plate assay. Biotinylated SAP bound to immobilized HDL and VLDL in a calcium dependent, saturable manner.Results: The SAP HDL and SAP VLDL bindings reached saturation at 4nM and 16nM of SAP, respectively. The bindings were inhibited by native SAP in a dose dependent manner. No binding between SAP and LDL was found in the presence of calcium or EDTA, which indicates the specificity of SAP lipoprotein interactions. Conclusion: These results suggest that the function of SAP is related to its capability to interact with lipoproteins and this may have important implications in atherosclerosis and in amyloids.更多还原