代谢
使用环-(14)C-标记的异丙隆(1微克/升),研究了异丙隆进入Bombina bombina和Bombina variegata的卵块和蝌蚪的摄取情况。24小时后,发现每克新鲜重量的胚胎中有2%的放射性物质。结果表明,卵块的凝胶状物质并不能作为一个足够的物理屏障来保护胚胎免受异丙隆(IPU)的摄取和影响。在蝌蚪体内,通过细胞色素P-450系统对环-(14)C-标记IPU的代谢进行了分析。检测到了IPU的不同代谢物,如N-去甲基化和C-羟基化衍生物,以及烯丙基代谢物。在B. variegata的蝌蚪中,经过IPU处理后,测量了微粒体和可溶性谷胱甘肽-S-转移酶(sGSTs)对不同模型底物的活性。sGST的活性随着IPU引起的应激增加而增加,这取决于暴露时间和剂量。与纯活性成分IPU相比,含有IPU和乳化剂的商业苯脲类除草剂Tolkan Flo也显著提高了酶促反应。
Using ring-(14)C-labeled isoproturon (1 ug/L), the uptake into spawn and tadpoles of Bombina bombina and Bombina variegata was investigated. Two percent of the applied radioactivity was found per gram fresh weight in the embryo after 24 hr. Results indicate that the jelly mass of the spawn does not act as a sufficient physical barrier for protection against the uptake and influence of isoproturon (IPU) on the embryo. In vivo metabolism of ring-(14)C-labeled IPU by the cytochrome P-450 system was analyzed in tadpoles. Different metabolites of IPU, such as N-demethylated and C-hydroxylated derivatives, and the olefinic metabolite were detected. In tadpoles of B. variegata, the activity of microsomal and soluble glutathione-S-transferase (sGSTs) toward different model substrates was measured after treatment with IPU. Activities of sGST increased corresponding to elevated stress by IPU dependent on exposure time and dose. Compared to the pure active ingredient IPU, the commercial phenyl-urea herbicide Tolkan Flo, consisting of IPU and an emulsifier, also caused significantly elevated enzymatic response.
来源:Hazardous Substances Data Bank (HSDB)