Hammond A H, Fry J R
Department of Physiology and Pharmacology, Medical School, Queen's Medical Centre, Nottingham NG7 2UH, UK.
Toxicol In Vitro. 1991;5(2):133-7. doi: 10.1016/0887-2333(91)90033-a.
Hepatocytes from control, phenobarbitone- and beta-naphthoflavone-treated rats were cultured for 24 hr and then exposed to seven known hepatotoxins: butylated hydroxytoluene, valproic acid, 2-methylfuran, 4-ipomeanol, 6-thiopurine and precocenes I and II. After a further 24 hr in culture, cell survival was determined by assaying mitochondrial reduction of MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]. All the compounds, except 4-ipomeanol, were more toxic to hepatocytes cultured from phenobarbitone-treated rats than to hepatocytes from either control or beta-naphthoflavone-treated rats. The toxicity of 4-ipomeanol was increased to a similar extent by both inducers. Although to a lesser extent than phenobarbitone, beta-naphthoflavone treatment in vivo increased the toxicity in vitro of all the other test compounds except valproic acid and butylated hydroxytoluene. In general the observed changes in toxicity agreed with in vivo data in the literature. When rat hepatocytes were treated in vitro with phenobarbitone or beta-naphthoflavone, 4-ipomeanol was not toxic to either control or phenobarbitone-treated cultures, although some toxicity was detected in the beta-naphthoflavone-treated cultures. Precocene II was not toxic to the control cultures but was toxic to both phenobarbitone- and beta-naphthoflavone-treated cultures. However, as with 4-ipomeanol, the enhancement of toxicity after induction in vitro, particularly with phenobarbitone, was much reduced compared with treatment in vivo. The results suggest that hepatocytes cultured from inducer-treated rats can be used as a model for the investigation of P-450-mediated toxicity in vitro.
将来自对照组、经苯巴比妥和β-萘黄酮处理的大鼠的肝细胞培养24小时，然后暴露于七种已知的肝毒素：丁基化羟基甲苯、丙戊酸、2-甲基呋喃、4-异吡唑甲醇、6-硫嘌呤以及早熟素I和早熟素II。在进一步培养24小时后，通过检测MTT [3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐] 的线粒体还原情况来确定细胞存活率。除4-异吡唑甲醇外，所有化合物对经苯巴比妥处理的大鼠培养的肝细胞的毒性均比对对照组或经β-萘黄酮处理的大鼠的肝细胞的毒性更大。两种诱导剂均使4-异吡唑甲醇的毒性增加到相似程度。虽然程度低于苯巴比妥，但体内β-萘黄酮处理增加了除丙戊酸和丁基化羟基甲苯外所有其他受试化合物的体外毒性。总体而言，观察到的毒性变化与文献中的体内数据一致。当大鼠肝细胞在体外用苯巴比妥或β-萘黄酮处理时，4-异吡唑甲醇对对照组或经苯巴比妥处理的培养物均无毒性，尽管在经β-萘黄酮处理的培养物中检测到了一些毒性。早熟素II对对照培养物无毒，但对经苯巴比妥和β-萘黄酮处理的培养物均有毒性。然而，与4-异吡唑甲醇一样，与体内处理相比，体外诱导后毒性的增强，尤其是用苯巴比妥诱导后，大大降低。结果表明，来自经诱导剂处理的大鼠的培养肝细胞可作为体外研究P-450介导的毒性的模型。
