鲫鱼肝脏微粒体ＣＹＰ４５０同工酶对多溴联苯醚胁迫的应答

以鲫鱼(Carassius aztratus Linn.)为试验鱼类,研究了其暴露于不同浓度的2,2',4,4'-四溴联苯醚(PBDE-47)和十溴联苯醚(PBDE-209)后鱼肝微粒体中CYP450同工酶活性的动态变化.结果表明,鲫鱼在0.10-5.00 mg·L~(-1)的PBDE-47和5.00～50.0 mg·L~(-1)的PBDE-209中暴露15 d后,其肝脏微粒体中CYP450系的同工酶CYP1A1被诱导,呈显著的剂量-效应关系.CYP1A1的活性随着作用时间的延续而上升,到试验第15 d时达到最高,但上升速率最快的阶段为试验后的0～5 d.而CYP450系的同工酶CYP1A2则表现出不同的特点,即低浓度PBDEs试验组对CYP1A2无显著影响(P>0.05),但5.00mg·L~(-1)PBDE-47、30.0和50.0mg·L~(-1)PBDE-209浓度组的鱼肝微粒体CYP1A2活性受到了轻微的抑制,最大抑制率分别为6.48%、3.48%和7.23%.研究表明,鱼类肝脏微粒体中CYP450的同工酶可作为污染生物标志物来评价PBDEs的早期污染毒理效应.

Responses of CYP450 Isoenzyme in Liver Microsome of Carassius auratus Linn.Under Polybrominated Diphenyl Ethers Stress

This article takes Carassius auratus Linn as an experimental subject and researches on its dynamic change of isoenzyme activity ex-isting in CYP450 of liver microsome when Carassius auratus Linn is exposed under the different consistency of tetrabromodiphenyl ether (PBDE-47) and decabromodiphenyl ether(PBDE-209). The results show that the isoenzyme(CYPlAl ) of CYP450 existing in the liver mi-crosome is induced and has obvious dosage-effect relationship when Carassius auratus Linn is exposed under the PBDE-47 (0.10~5.00 mg· L~(-1)) and PBDE-209 (5.00~50.0 mg·L~(-1)) 15 days.The activity of CYP1A1 will rise with the perdurability, and this rise will reach apogee in the 15th day. However, the fastest rise speed will happen in 0~5 days after the experiment. Compared with this, the isoenzyme (CYP1A2) of CYP450 has different character that is experimental group named PBDEs with light concentration has no obvious influence on CYP1A2(P> 0.05), but the activity of CYP1A2 is inhibited gently under 5.00 mg·L~(-1) PBDE-47, 30.0 mg·L~(-1) and 50.0 mg·L~(-1) PBDE-209. The maximum suppression ratio are 6.48%, 3.48% and 7.23%. The research result is that the isoenzyme of CYP450 existing in fish liver microsome can be taken as the better pollution- biomarkers to evaluate the toxicity effect of precontamination of PBDEs.