重金属铬对黑斑蛙胚胎和蝌蚪生长发育的影响及血细胞DNA损伤效应

Effect of Potassium Dichromate on the Development of Embryo and Tadpole of Frog,Rara nigromaculata,and on DNA Damage

运用单细胞凝胶电泳技术研究了不同浓度重铬酸钾(K2Cr2O7)溶液(2.5,12.5,62.5μmol.L-1)对黑斑蛙(Rara nigromaculata)外周血细胞DNA的链断裂损伤效应,并观察了重铬酸钾对黑斑蛙胚胎和蝌蚪生长发育的影响.结果表明,12.5和62.5μmol.L-1的重铬酸钾具有明显的DNA链断裂损伤诱导效应,染毒15 d的DNA损伤率分别为85%和98%.在测试浓度范围内,重铬酸钾对黑斑蛙胚胎发育的影响不明显;低浓度<(12.5μmol.L-1)重铬酸钾对黑斑蛙蝌蚪生长发育的影响不明显,高浓度(62.5μmol.L-1)重铬酸钾对黑斑蛙蝌蚪的生长发育则具有明显的抑制作用.

The effects of potassium dichromate （K2Cr2O7） （2.5, 12.5 and 62.5μmol·L^-1） on DNA strand breaks damage of peripheral haemocyte of frog, Rara nigromaculata, were investigated with single cell gel electrophoresis assay （SCGE）, and the effect of K2Cr2O7 on development of embryo and growth of tadpole of frog were examined. The results show that K2Cr2O7 in 12.5 and 62.5μmol·L^-1 can induce DNA strand breaks damage of frog＇s peripheral haemocyte, amount of cells damaged up to 85% after intoxication for 15d. Treatment with K2Cr2O7 did not interfere the frog＇s embryo development at the tested concentrations. With respect to growth of frog＇s tadpole, K2Cr2O7 at low concentration （（12.5μmol·L^-1） shows weakly inhibition, and K2Cr2O7 at high concentration （62.5μmol·L^-1） show significant inhibition.