• 作者： 翁祖輝; 翁芸芳; 劉英修; 林仁混; 李信徹
• 作者服務機構： 國立臺灣大學醫學院毒理學研究所與生化研究所; 中央研究院動物學研究所
• 中文摘要： 吳郭魚經多氯聯苯 Aroclor1254 處理後，肝微粒體細胞色素P-450及b ，含量分別增加60%及36%，同時，苯駢芘羥化
  ?及7-ethoxyresorufin O-去乙基?活性分別升高14倍及18倍。多氯聯苯預處理使7－乙氧基香豆素去乙基?活性增加50%
  ，但不影響雙甲基亞硝基胺去甲基?及NADPH－細胞色素C還原?活性。多氯聯苯對吳郭魚單氧?的誘導作用與3－甲基
  膽?之作用相似。相反的，苯巴比妥預處理對吳郭魚單氧?系統組成?及催化活性皆無作用。光譜分析結果顯示對照組
  肝微粒體一氧化碳差異光譜之最高吸收峰波長在450nm，多氯聯苯及3－甲基膽?實驗組之最高吸收峰波長則轉移至
  449nm，苯巴比妥組無此光譜轉移現象。電泳分析結果顯示多氯聯苯及3－甲基膽?預處理使微粒體在P-450分子量區域
  中一種蛋白染色帶濃度增加，苯巴比妥則無此效應。由這些實驗結果得知吳郭魚單氧?系統可被多氯聯苯及3－甲基膽?
  誘導，但對苯巴比妥卻無反應。淡水河捕獲之吳郭魚及其他魚種實驗結果顯示污染水域魚類苯駢芘經化?活性較未污染
  水域者為高。
  的
• 英文摘要： Pretreatment of tilapias with a polychlorinated biphenyl mixture, Aroclor 1254, caused 60% and 36%increases of cytochromes P-450 and b contents in liver microsomes, respectively. The increases of thehemoproteins were associated with 14- and 18-fold induction of benzo(a)pyrene hydroxylase and 7-ethoxy-resorufin O-deethylase activities, respectively. Pretreatment with Aroclor 1254 caused a 50% increase of7-ethoxycoumarin O-deethylase activity without affecting N-nitrosodimethylamine demethylase orNADPH-cytochrome c reductase activities. The inductive effects of Aroclor 1254 on tilapia monooxy-genase were similar to the effects of 3-methylcholanthrene. In contrast, pretreatment with phenobarbitalhad no significant effect on the enzyme components and catalytic activity of the tilapia monooxygenasesystem. Spectral analysis of liver microsomes showed that the Soret maximum in the CO-differ-ence spectrum shifted from 450 nm in control fish to 449 nm in Aroclor 1254- and 3-methylcholanthrene-treated animals. No such spectral shift was observed with phenobarbital-treated tilapias. Gel electrophoresisof the microsomes revealed that Aroclor 1254 and 3-methylcholanthrene caused apparent increases in theintensity of a protein band(s) in the cytochrome P-450 molecular weight region. Pretreatment with pheno-barbital had no effect on the electrophoretic property of liver microsomes. The xenobiotic inductionstudies have demonstrated that the tilapia monooxygenase system is responsive to the stimulatory effectsof polychlorinated biphenyls and 3-methylcholanthrene, but not phenobarbital. The results of feral fishstudies have shown that benzo(a)pyrene hydroxylase activities of wild tilapia and other fish from pollutedsections of the Damsui River were elevated, relative to the activities of fish from nonpolluted water.
• 中文關鍵字： ploychlorinated biphenyls; 3-methylcholanthrene; cytochrome P-450; monooxygenase; enzyme induction; tilapia
• 英文關鍵字： --