
戊吡虫胍对棉铃虫中枢神经细胞电压门控钙通道和钾通道的影响
Effects of Guadipyr on voltage-gated calcium and potassium channels in central neurons of Helicoverpa armigera
关丹阳;姜笑维;李清亚;刘 晓;马永强;陈 强 ;Li-Byarlay Hongme
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DOI:10.7679/j.issn.2095-1353.2020.086
作者单位:南开大学生命科学学院,生物活性材料教育部重点实验室; 中国农业大学理学院应用化学系;中央州立大学农业与生命科学系农业研究与开发计划
中文关键词:戊吡虫胍;棉铃虫;电压门控Ca2+通道;电压门控K+通道;全细胞膜片钳
英文关键词:Guadipyr; Helicoverpa armigera; voltage-gated calcium channels; voltage-gated potassium channels; Whole-cell Patch Clamp Technique
中文摘要:
【目的】 戊吡虫胍是将新烟碱类和缩氨脲类杀虫剂杀虫活性部分重新组合的新型杀虫剂。但对于该类杀虫剂究竟如何影响离子通道,通道门控特性和功能是如何变化目前尚未见报道。本实验旨在明确该杀虫剂是否影响电压门控钙通道和钾通道的门控过程,探究其是否为该杀虫剂的潜在作用靶标。 【方法】 应用全细胞膜片钳技术检测戊吡虫胍对棉铃虫Helicoverpa armigera Hübner中枢神经细胞电压门控Ca2+通道和K+通道的影响。【结果】 戊吡虫胍作用后Ⅰ-Ⅴ曲线和激活曲线均向超极化方向移动10-15 mV,具有显著性统计学差异(P<0.05)。稳态失活曲线向超极化方向移动约5 mV,不具有统计学差异(P>0.05)。电压门控Ca2+通道峰值电流(Ipeak)有不同程度的降低。随着浓度增大Ipeak降低有减小的趋势。此外,1 μmol∙L-1戊吡虫胍作用后钙离子的窗口电流(Iw)面积增加幅度较10 μmol∙L-1和100 μmol∙L-1大,为93.20%。提示在一定的测试电压下,该药物作用后处于激活状态的Ca2+通道数目增多。另外,其作用后电压门控钾通道Ipeak降低。随着浓度增大Ipeak降低有减小的趋势。同时Ⅰ-Ⅴ曲线下移,激活曲线向去极化方向移动约8 mV,不具有统计学差异(P>0.05)。这表明戊吡虫胍作用后K+通道在较高电位下才能激活。【结论】 戊吡虫胍能够有效抑制Ca2+通道和K+通道Ipeak,并使通道的激活曲线和失活曲线发生移动,影响Ca2+通道和K+通道的门控特性。表明棉铃虫中枢神经细胞上的电压门控Ca2+通道和K+通道是戊吡虫胍的潜在作用靶标之一。
英文摘要:
[Objectives] Guadipyr is a novel insecticide that has both
neonicotinoid and semicarbazone insecticidal activity. How it affects ion
channels and channel gating characteristics and functions is currently unknown. We examined the effects of Guadipyr on
voltage-gated calcium and potassium channels, and explored whether these
channels are potential targets for this pesticide. [Methods] The effects of
three concentrations (1, 10, and 100 μmol∙L-1) of Guadipyr on Ca2+and
K+ channels were studied using the patch clamp technique. [Results] All three concentrations of Guadipyr
significantly (P<0.05) shifted Ca2+ channel Ⅰ-Ⅴ and activation curves about 10-15 mV in the
negative direction. The inactivation curves of Ca2+ channels were
also shifted 5 mV towards the hyperpolarizing direction, which is a not
significant shift (P>0.05). The Ca2+ peak current was
significantly decreased by Guadipyr treatment relative to the control. The Ipeak decreased more slowly as the concentration of Guadipyr increased. The area of
window current increased the most (93.20%) following treatment with 1 μmol∙L-1 Guadipyr than by
treatment with 10 μmol∙L-1 and 100 μmol∙L-1. The number of Ca2+ channels activated increased after
Guadipyr treatment at a test voltage of ﹣60 mV to +10 mV. The K+ peak current decreased gradually when
Guadipyr was added to the external solution; the Ipeak decreased
more slowly as the Guadipyr concentration increased from 10 μmol∙L-1 to 100 μmol∙L-1. Ⅰ-Ⅴ curves declined and the activation of K+ channels
was shifted 8 mV towards the depolarizing direction, which was not significant
(P>0.05). This shows that K+ channels can be activated at
higher potentials by Guadipyr. [Conclusion] Guadipyr can effectively inhibit the Ipeak of the Ca2+and K+ channels, and shift the activation and
inactivation curves of these channels, thereby affecting the gating of Ca2+ channels and K+ channels. Therefore, Ca2+ and K+ channels in the central neurons of H. armigera are potential Guadipyr target
sites.