• 作者： 翁祖輝; 朱致民; 蔡振寧
• 作者服務機構： 國立臺灣大學醫學院生化學研究所
• 中文摘要： 本實驗探討長期餵養乙醇對田鼠肝、腎、腸單加氧?之影響。餵養田鼠含乙醇之液體飼料二週後，肝及腎微粒體之
  苯胺羥化?活性即增加並趨至最高水平，而小腸苯胺羥化?活性則無增加。對照組及餵食乙醇組之田鼠中，肝及非肝組
  織微粒體一氧化碳差異光譜之最高吸收峰波長不同。長期餵食乙醇促使田鼠肝及腎細胞色素P-450及b5之含量增加，並
  使微粒體中苯胺羥化，雙甲基亞硝基胺去甲基及7-乙氧基香豆素去乙基等單加氧?之活性升高。相反的，在小腸中，
  餵食乙醇降低微粒體之細胞色素P-450及b5含量，乙醇對小腸之苯胺，雙甲基亞硝基胺，7-乙氧基香豆素及苯芘單加
  氧?代謝活性則無影響。聚丙烯醯胺膠電泳實驗結果顯示餵食乙醇增加肝、腎微粒體蛋白在細胞色素P-450分子量區域
  染色帶之濃度，而對照組及餵食乙醇組動物之小腸微粒體蛋白染色帶濃度則無顯著分別。以上結果得知乙醇對田鼠單加
  氧?誘導能力有組織特異性，此特性在衡量乙醇對於不同器官中外來物代謝與毒性之影響可能是一重要因子。t
• 英文摘要： The effects of ethanol on liver, kidney and intestine monooxygenases were studied using hamsterschronically fed with isocaloric control and ethanol-containing liquid diets. The inductive effects of ethanolon liver and kidney aniline hydroxylase activities began to approach plateau level after the animals werefed ethanol for two weeks. Intestinal aniline hydroxylation was refractory to ethanol induction. In controland ethanol-fed hamsters, CO-difference spectra of hepatic and extrahepatic microsomes differed in ab-sorption maxima. Chronic alcohol consumption caused significant increases of cytochrome P-450 andcytochrome b5 contents of liver and kidney microsomes. The increases of the heme proteins were associatedwith the induction of aniline hydroxylase, N-nitrosodimethylamine demethylase and 7-ethoxycoumarin0-deethylase activities. In contrast to the liver and kidney, intestinal microsomal cytochromes P-450and b5 contents in ethanol-treated animals were lower than the controls. Ethanol pretreatment was withouteffect on intestinal monooxygenase activities toward the metabolism of aniline, N-nitrosodimethylamine,7-ethoxycoumarin and benzo(a)pyrene. Gel electrophoresis of tissue microsomes from control and ethanol-treated hamsters revealed that ethanol treatment enhanced the intensity of the protein band(s) in thecytochrome P-450 molecular weight region in the liver and kidney, but not in the intestine. These resultsdemonstrate that in hamsters the response of monooxygenase to ethanol may vary from tissue to tissueand it is difficult to make a generalization regarding the inducing property of ethanol. The differentialeffect on cytochrome P-450 may be an important factor in determining the interaction between ethanoland xenobiotic metabolism in animal tissues.
• 中文關鍵字： ethanol; cytochrome P-450; monooxygenase; regulation; hamster; tissue
• 英文關鍵字： --