蛋白水解法测定天冬氨酸转氨酶同工酶

The study of proteolytic assaying AST isoenzymes in serum

胰凝乳蛋白酶时天冬氨酸转氨酶胞质同工酶（ｃ一ＡＳＴ）有很强的选择性水解失活作用，而对其线粒体同工酶（ｍ一ＡＳＴ）无此作用。利用这一原理，建立了一种ｍ一ＡＳＴ测定力法，其优点是准确、方便、快速、经济，并适合仪器自动化分析，ＣＶ可达到２．２４％，参考值（ｘ±ｓ）为７．６０±３．６２Ｕ／Ｌ。延用ＩＦＣＣ推荐的ＡＳＴ测定条件，可间接获得ｃ一ＡＳＴ活性。同时发现伴ＡＳＴ增高的肝癌病例中，ｍ一ＡＳＴ可占总ＡＳＴ活性的８１．１％。

hymotrypsin has a highly selective inactivating effect on the cytoplasmic isoenzyme(c-AST),but does not have the same effect on the mitochondrial isoenzyme(m一AST)of aspartate aminotransferase.The authors established a new method for determination of m一AST in serum The advantages of the proteolytic assay are accurate,convenient,swift.economical and suita ble for automation This method adopted the condition of AST assay recommended by IFCC,and can obtain the activaty of c一AST indriectly,CV of the method is 2.24%,the nonnal value region is 7.60±3.62 U/L.In the anthor's records,the proportion of m一AST to'total'AST is 81.1%in thepatients with cancer of the liver