文献类型：期刊文献

中文题名：酶法测定卵磷脂胆固醇酰基转移酶活性

英文题名：Determination of Lecithin:cholesterol Acyltransferase Activity by An Enzymatic Method

作者：钱江潮[1];龚邦强[2];曹进新[2];张嗣良[1]

机构：[1]华东理工大学国家生化工程技术研究中心,上海200237;[2]上海医药集团总公司,上海200010

年份：2003

卷号：29

期号：2

起止页码：152

中文期刊名：华东理工大学学报（自然科学版）

外文期刊名：Journal of East China University of Science and Technology

收录：CSTPCD;;EI(收录号：2003257514405);Scopus;北大核心:【北大核心2000】；CSCD:【CSCD2011_2012】；

语种：中文

中文关键词：卵磷脂胆固醇酰基转移酶;LCAT;酶活测定;药物筛选;胆固醇;逆向运输;测定方法

外文关键词：lecithin∶cholesterol acyltransferase (LCAT); enzyme activity determination; drug screen

摘要：催化血浆中游离胆固醇酯化反应的卵磷脂胆固醇酰基转移酶(LCAT)是胆固醇逆向运输过程中的关键酶之一。本研究针对原测定方法中本底过高的问题,改变了对照本底的反应条件,使原反应体系中的前两步酶反应无法进行,最终测得的反应速率真实地反映了样品中本底(甘油-3-磷酸)的水平。经改进的测定方法除成功地用于人血清测定外,还应用于细胞培养液和兔血清的测定,对于相关药物的研究和筛选具有实际应用价值。
Lecithin:cholesterol acyltransferase (LCAT) is a key enzyme in reverse cholesterol transport, which catalyzes the esterification of free cholesterol in human plasma. In most of the methods, an artificial liposome is served as the substrate for LCAT and the enzyme activity is measured by the radioactivity incorporated into the cholesterol ester generated, which limits the use of LCAT assay in clinical test and drug screening with a large number of samples. LCAT activity was determined by an endogenous selfsubstrate method in a series of enzyme catalyzed reactions developed by Imamura Shigeyuki with an extraordinarily high blank level. To resolve this problem, the reaction system was investigated and it was found that the incomplete inhibition of LCAT activity by Triton X100 resulted in the unusual phenomenon. So, the first two enzymatic reactions following the LCAT catalyzed reaction were omitted in the blank measurement, and the NADH reduction was only due to the glycero3phosphate present in the sample solution. After the improvement, this system was applied successfully in cell culture medium and rabbit serum. So, this is a practical method in drug screening and other fields related to LCAT metabolism.