人羊膜细胞FL系中细胞色素P450同功酶的诱导

Induction of cytochrome P450 isozymes in human amnion FL cells

人羊膜细胞FL系含有低水平的基础EROD,ECOD和APND活性,其中EROD活性可被3—MC,β—NF及NE诱导达对照的3.1～6.7倍;ECOD和APND活性则不仅可被上述三种诱导剂还可被PB所诱导,分别增加到2～3和1.5～2倍的活性。当用3—MC与NE同时处理细胞时,EROD和APND活性的升高明显强于3—MC单独处理时。在诱导剂撤除后,细胞内EROD和ECOD的活性维持诱导后的高水平达24～36 h之久。提示诱导后一定时间内细胞对外来化合物的代谢能力明显增强。

The human FL cell line contains low levels of constitutive ethoxyresorufin O-deethylase(EROD),7-ethoxycoumarin-O-deethylase(ECOD)and aminopyrine N-demethylase(APND)activities,among which EROD could be induced by nore-pinephrine hydrochloride(NE),β-naphthoflavone(β-NF)and 3-methylcholanthrene(3-MC),while ECOD and APND activities could be induced by NE,β-NF and 3-MC as well as PB.The inducibilities of EROD,ECOD and APND were 3.1-6.7,1.8-3.1 and 1.4-2.0 times of controls,respectively.Co-treatment with 3-MC and NE resulted in higher EROD and APND activities than treatment with 3-MC alone.The induced EROD and ECOD activities remained at a high level for 24-36 h after removal of the inducer from the medium.It is suggested that the metabolizing ability of the induced FL cells are stronger than that of the uninduced ones in a given time following induction.From the viewpoint of enzymology,the results further confirm that feasible is the design of directly using the cytochrome P450 isozyme of the induced FL cell as a biological indicator in short-term test for screening promutagens/procarcinogens.