The objective of this research was to investigate the potential damage caused by the residual concentrations of the insecticides Regent^® WS 800 and Curbix^® SC 200, containing fipronil and ethiprole, respectively as active ingredients, on the liver of Oreochromis niloticus. The analyses of HSP70 shock protein labelling and cell death process by TUNEL method were performed in order to measure the effects of the exposure of cell repair system of fish to both insecticides. Statistical analyses showed no significant molecular damage to the hepatic tissue of animals. Nevertheless, variations in HSP70 and DNA fragmentation levels, endpoint of cell repair system response and cellular death, respectively, were observed in several groups. These results indicate that the cell repair machinery was efficient when in contact with residual concentrations of insecticides. However, the DNA fragmentation detected by the TUNEL method suggests that even in face of the cytoprotective action of the HSP70 protein, there are damages that become irreparable. To finish, it is worth mentioning that given the results obtained from residual concentrations, use in the field should be with caution.

本研究的目的是调查引起杀虫剂摄政的残留浓度的潜在损害^® WS 800和Curbix ^® SC 200，分别包含氟虫腈和乙虫腈，作为活性成分，在肝脏罗非鱼。采用TUNEL法对HSP70休克蛋白标记和细胞死亡过程进行了分析，以测定鱼类细胞修复系统对两种杀虫剂的暴露影响。统计分析表明对动物肝组织没有明显的分子损伤。然而，在几组中分别观察到HSP70和DNA片段化水平，细胞修复系统应答终点和细胞死亡的变化。这些结果表明，当与残留浓度的杀虫剂接触时，细胞修复机制是有效的。但是，通过TUNEL方法检测到的DNA片段表明，即使面对HSP70蛋白的细胞保护作用，也存在无法弥补的损害。完成，