Nikiforov A A, Ivanova E M, Alksnis E G
Biull Eksp Biol Med. 1985 Feb;99(2):158-61.
A study was made of the kinetics of the lecithin-cholesterol-acyltransferase reaction (LCAT-reaction) according to the substrate, nonesterified cholesterol of high density lipoproteins (HDLP) and of the effect produced by the medium pH and apoprotein E (apo-E) on the rate of the LCAT-reaction in blood plasma of subjects with hyper-alpha-lipoproteinemia. HDLP isolated from blood plasma of subjects with hyper-alpha-lipoproteinemia were used as substrate. Infranatants obtained from blood plasma of the test subjects after removing all lipoproteins with a density of 1.21 g/ml served as a source of the enzyme. The kinetic curve of the rate of the LCAT-reaction with one or two plateaus was found to be complex in nature; pH 7.4 and 8.0 were found to be optimal for the LCAT-reaction at high and low concentrations of HDLP, respectively. At a low HDLP concentration apo-E had no remarkable effect on the rate of the LCAT-reaction, while at a high HDLP concentration the rate of the LCAT-reaction was increased. It is assumed that more than two isoforms of LCAT are present in blood plasma of subjects with hyper-alpha-lipoproteinemia.
针对高α脂蛋白血症患者血浆中卵磷脂 - 胆固醇酰基转移酶反应（LCAT反应）的动力学进行了研究，该反应以高密度脂蛋白（HDLP）的非酯化胆固醇为底物，并探讨了介质pH值和载脂蛋白E（apo - E）对LCAT反应速率的影响。从高α脂蛋白血症患者血浆中分离出的HDLP用作底物。将测试对象血浆中去除所有密度为1.21 g/ml的脂蛋白后得到的上清液用作酶源。发现LCAT反应速率的动力学曲线本质上很复杂，有一个或两个平台期；pH 7.4和8.0分别被发现是高浓度和低浓度HDLP时LCAT反应的最佳pH值。在低HDLP浓度下，apo - E对LCAT反应速率没有显著影响，而在高HDLP浓度下，LCAT反应速率增加。据推测，高α脂蛋白血症患者血浆中存在两种以上的LCAT同工型。
