Miwa M, Kubota I, Ichihashi T, Motojima H, Matsumoto M
J Biochem. 1984 Sep;96(3):761-73. doi: 10.1093/oxfordjournals.jbchem.a134894.
Phospholipase A inhibitor was found in bovine, human and porcine plasma. The inhibitor was purified about 300-fold from bovine plasma by ammonium sulfate fractionation, DEAE-cellulose chromatography, Sephadex G-200 gel filtration and anti-BSA antibody-agarose column chromatography to remove albumin. The purified material was homogeneous as judged by immunoelectrophoresis and 0.7% agarose-2% polyacrylamide gel electrophoresis. The inhibitor suppressed not only rat and human plasma phospholipase A2 activity, but also purified Mamushi (Agkistrodon halys blomhoffi) venom phospholipase A2-II. Bovine plasma inhibitor was shown to be a lipoprotein containing phosphatidylcholine, sphingomyelin, cholesterol ester, and triacyl glycerol as major lipid components. The molecular weight of the native inhibitor was nearly the same as that of bovine plasma high density lipoprotein (HDL) when determined by the gel filtration method. The molecular weights of two subunits of the inhibitor observed on polyacrylamide gel electrophoresis in the presence of SDS were about 10K and 42K. The anti-inhibitor antiserum obtained from rabbits immunized with the highly purified inhibitor cross-reacted with bovine plasma alpha-lipoprotein (HDL). The lipid composition of the inhibitor was similar to that of HDL, but apoinhibitor and apoHDL were different in molecular weight and solubility in various buffers.
在牛、人及猪血浆中发现了磷脂酶A抑制剂。通过硫酸铵分级分离、DEAE - 纤维素柱色谱、葡聚糖凝胶G - 200凝胶过滤及抗牛血清白蛋白抗体 - 琼脂糖柱色谱从牛血浆中纯化该抑制剂约300倍以去除白蛋白。经免疫电泳和0.7%琼脂糖 - 2%聚丙烯酰胺凝胶电泳判断，纯化后的物质是均一的。该抑制剂不仅抑制大鼠和人血浆磷脂酶A2活性，还抑制纯化的蝮蛇（Agkistrodon halys blomhoffi）毒液磷脂酶A2 - II。牛血浆抑制剂被证明是一种脂蛋白，其主要脂质成分包含磷脂酰胆碱、鞘磷脂、胆固醇酯和三酰甘油。通过凝胶过滤法测定时，天然抑制剂的分子量与牛血浆高密度脂蛋白（HDL）的分子量几乎相同。在SDS存在下聚丙烯酰胺凝胶电泳上观察到的抑制剂的两个亚基的分子量约为10K和42K。用高度纯化的抑制剂免疫兔子获得的抗抑制剂抗血清与牛血浆α - 脂蛋白（HDL）发生交叉反应。抑制剂的脂质组成与HDL相似，但脱辅基抑制剂和脱辅基HDL在分子量和在各种缓冲液中的溶解度方面有所不同。
