三氟氯氰菊酯对棉铃虫神经细胞延迟整流钾电流的抑制作用

用膜片钳技术首次研究了三氟氯氰菊酯对离体培养的棉铃虫中枢神经细胞延迟整流钾通道电流的影响。结果表明，药物作用前有81%和39%的细胞的通道分别在-30 mV 和 -40 mV 激活（n=21）。三氟氯氰菊酯（10^-5 mmol/L）作用15 min后，有63%和38%细胞的通道分别在-40 mV 和 -50 mV 激活（n=8）；作用1 min后电流幅值明显降低，抑制率达到了37.7%（n=19）；加药后激活曲线明显左移且Vh 值变化显著，但k值没有明显变化。实验结果说明，三氟氯氰菊酯作用后，通道更容易激活，但显著抑制电流峰值，导致神经敏感性降低，棉铃虫中枢神经细胞钾通道也是拟除虫菊酯类药物的作用靶标之一。

Inhibition effects of cyhalothrin on the delayed rectifier potassium current in the central neurons of Helicoverpa armigera

The effects of cyhalothrin on the delayed rectifier potassium current in the central neurons of Helicoverpa armigera were studied using the patch clamp technique for the first time. The results showed that before application of cyhalothrin, 81% and 39% cells were activated at-30 mV and-40 mV (n=21), respectively. In 15 min after cyhalothrin (10 -5 mmol/L) application, 63% and 38% cells were activated at-40 mV and-50 mV (n=8), respectively. The amplitude of the current decreased significantly after application of cyhalothrin and the inhibition percentage reached 37.7% in 1 min (n=19). After the application, activation curve shifted to the negative direction and the value of V_h changed significantly, but the k value did not change remarkably. In conclusion, the results suggest that under the action of cyhalothrin, the potassium channels can be activated more easily and current amplitude can be inhibited significantly, this is related to the nervous insensitivity, and potassium channels of Helicoverpa armigera central neurons are the action targets of pyrethroid insecticides.