Clay P, Cross M F
ICI Central Toxicology Laboratory, Macclesfield, Cheshire, UK.
Mutagenesis. 1990;5 Suppl:45-54.
As part of the third UKEMS collaborative trial, ICI Central Toxicology Laboratory (CTL) tested the three study chemicals ethylmethanesulphonate (EMS), benzo[a]pyrene (B[a]P) and benzidine (BZD) in a microwell adaptation of the L5178Y gene mutation assay using the thymidine kinase (tk) locus. Cofactors for metabolic activation were optimized prior to testing the chemicals under differing expression times (48 and 72 h) and S9 levels (2,5 and 10%). The results for zero hour survival, relative total growth and mutant frequency were subjected to extensive statistical analyses. It was concluded that the methods described produce a robust and reliable assay and that for routine use a single 72 h expression time and 5% S9 level are sufficient, provided true independent replicates are used.
作为英国环境诱变剂学会（UKEMS）第三次合作试验的一部分，帝国化学工业公司中央毒理学实验室（ICI CTL）采用胸苷激酶（tk）基因座，通过微孔板改良的L5178Y基因突变试验，对三种受试化学物质甲磺酸乙酯（EMS）、苯并[a]芘（B[a]P）和联苯胺（BZD）进行了测试。在不同表达时间（48小时和72小时）和S9水平（2%、5%和10%）下对化学物质进行测试之前，对代谢活化的辅助因子进行了优化。对零小时存活率、相对总生长率和突变频率的结果进行了广泛的统计分析。得出的结论是，所述方法可产生可靠且稳健的试验，并且对于常规使用而言，只要使用真正独立的重复样本，单一的72小时表达时间和5%的S9水平就足够了。
