• 환경생물
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• 제20권2호
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• pp.173-179
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• 2002

N-nitrosoethylurea(NEU)에 의한 지질 과산화물의 함량 변화와 알데히드 대사효소 및 항산화효소의 활성변화를 쥐 간세포에서 측정하였다. 알데히드 대사효소로는 alcohol dehydrogenase와 aldehyde dehydrogenase가 사용되었고 항산화효소로는 glutathione transferase, superoxide dismutase, glutathione reductase와 catalase가 사용되었다. 쥐 간세포에 다양한 농도의 NEU를 처리한 후 지질 과산화물의 함량변화를 측정하였다. 그 결과 6.25mM NEU에 의하여 지질 과산화물의 함량이 최대 2.5배 증가하였다. Alcohol dehydrogenase의 활성은 NEU처리에 의하여 대조군보다 최대 2.3배 증가하였고 aldehyde dehydrogenase의 활성은 약 2배 증가하였다. 전암성 병변의 지표로 이용되는 glutathione transferase와 catalase의 경우 NEU처리에 의한 활성증가가 미미하였다. 그러나 superoxide dismutase의 활성은 최대 1.5배 증가하였고, glutathione reductase의 활성은 약 3배 증가하였다. 그러므로 superoxide dismutase와 g1utathione reductase의 활성증가가 NEU의 독성에 대한 세포내 항산화 방어과정에서 중요한 역할을 할 것으로 추측된다

• Toxicological Research
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• 제18권3호
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• pp.293-300
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• 2002

Chemical carcinogen-induced alteration of aldehyde metabolic enzymes were examined in clone 9 cell. Diethylnitrosamine (DENA), N-nitrosoethylurea (NEU) and N-nitrosomorpholine (NNM) were wed as model carcinogens. Changes in enzyme activities by repetitive treatment of DENA, NEU or NNM were analyzed in terms of specific activities and activity stainings of the enzymes on the gel. Upon treatment of DENA, lipid peroxide level increased upto 10 fold, indicating strong oxidative stress state of the cell. Notable enhancement of ADH and ALDH activity occurred after DENA treatment, while glutathione-S-transferase activity was slightly increased. Furthermore, about 2.5 fold higher superoxide dismutase (SOD) activity was detected during deactivation of catalase (CAT) activity by repetitive treatment of DENA. However in NEU-treated cell, about 2.3 fold higher ALDH activity was found while ADH activity was slightly increased. Notable increase CAT and SOD could also be found. In contrast, maximum 3.5 fold higher CAT activity occurred during SOD deactivation in NNM-treated cell. These results suggest that there might be different enzymatic responses in relation to cell protection against DENA, NEU or NNM.