The effect of two heavy metals, namely chromium and cadmium, on GST and P450-MO activities in the liver, kidney and gut of the frog Rana ridibunda, and the use of these detoxification enzyme systems as possible markers of heavy metal contamination of rivers in Northern Greece was investigated. In control animals, the highest P450-MO activity was observed in the liver and the lowest activity in the gut. As regards GST, the liver and kidneys showed the highest activity. Exposure of Rana to either Cr or a mixture of Cr and Cd caused a decrease in liver GST and P450-MO and renal GST activities. An important finding was that both GST and P450-MO activities were negatively correlated with concentrations of both metals in the liver of mixture-exposed animals. The results suggest that the determination of GST and P450-MO activities, in combination, could serve to indicate heavy metal contamination in rivers of Northern Greece.

中文翻译：

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暴露于镉和铬的混合物对蛙蛙蛙的解毒酶（GST，P450-MO）活性的影响。

铬和镉这两种重金属对青蛙蛙蛙的肝脏，肾脏和肠道中GST和P450-MO活性的影响，以及使用这些解毒酶系统作为河流重金属污染的可能标志对希腊北部进行了调查。在对照动物中，在肝脏中观察到最高的P450-MO活性，而在肠道中观察到最低的活性。就商品及服务税而言，肝脏和肾脏的活性最高。Rana暴露于Cr或Cr和Cd的混合物中导致肝脏GST和P450-MO以及肾脏GST活性降低。一个重要发现是，GST和P450-MO活性均与混合暴露动物肝脏中两种金属的浓度呈负相关。结果表明，结合测定GST和P450-MO活性，