FL细胞中细胞色素P450同工酶的诱导及其在诱变剂生物学检测系统中的应用

INDUCTION OF CYTOCHROME P450 ISOZYMES IN FL CELL AND ITS APPLICATION IN SHORT-TERM BIOASSAYS FOR PROVIDING ACTIVATING SYSTEM

以AHH、FROD、ECOD及APND为标志酶、3-MC、β-NF、NE及PB为诱导剂证明人羊膜FL细胞系有可诱导的Cytp450IA及IB基因的表达,有较宽的药物代谢酶谱。EROD及APND的最大诱导反应见于3-MC与NE复合诱导时。基础和诱导的AHH具有Cytp448依存性混合功能氧化酶的特征。在诱导剂撤除后24-36h内,Cytp450同工酶的诱导活性仍维持在一较高水平。应用这种经过诱导的FL细胞在UDS及ADPRT介导的细胞NAD含量降低试验中确能代谢活化常见的前诱变剂/前致癌物。这种新设计可望取代肝微粒体代谢活化系统而用于诱变剂生物学检测。

The inducible expressions of genes of cytochrome IA and IIB in human amnion FL cell line was showed with 3-MC, beta-NF, NE and PB as inducer and AHH, EROD, ECOD and APND as marker end points. It is indicated that the FL cell has kept a broad spectrum of xenobiotic metabolizing enzymes .The highest inducing response was obtained in EROD and APND by 3-MC in combination with NE. Characteristics of cytochrome P448 dependent MFO has been showed aiso in FL cell both in the original and induced situations. The activity of the induced cytochrome P450 isozymes keeps at a high level for 36 hours at the least after the removal of the xenobiotic inducers from the culture medium. The capability of activating a variety of promutagens and procarcinogens was further demonstrated in FL cell with UDS and ADPRT assays in media with low cellular NAD content. Above mentioned results indicates the substitution of the hepatocyte microsome-NAD activation system by induced FL cell culture is feasible.