›› 2004, Vol. 47 ›› Issue (4): 429-433.

• 研究论文 • 上一篇    下一篇

cAMP和cGMP对棉铃虫神经细胞高电压激活钙通道的调节作用

李杰1,2,杜育哲1,佟帆1,贺秉军1,刘安西1   

  • 出版日期:2004-08-20 发布日期:2004-08-20

Modulations by cAMP and cGMP of the highvoltage activated Ca2+ channels in the central neurons of the cotton bollworm, Helicoverpa armigera

LI Jie1,2, DU Yu-Zhe1, TONG Fan1, HE Bing-Jun1, LIU An-Xi1   

  • Online:2004-08-20 Published:2004-08-20

摘要: 用全细胞膜片钳法研究了cAMP和cGMP对棉铃虫Helicoverpa armigera 3龄幼虫胸腹神经节细胞高电压激活钙通道的调节作用。细胞外液中加入腺苷酸环化酶(AC)激活剂福斯克林(forskolin) 0.1 mmol/L,对于Ba2+介导的钙通道电流激活电压、峰电压、峰电流变化以及通道激活和电流达到峰值的时间无影响。电极内液中加入1 mmol/L的cGMP则明显抑制峰电流,且抑制作用呈时间依赖性和浓度依赖性,而对激活电压、峰电压无影响。结果提示,棉铃虫神经细胞高电压激活钙通道的活动可能不受细胞内cAMP水平提高的影响,但被cGMP抑制。

关键词: 棉铃虫, 环磷酸腺苷, 环磷酸鸟苷, 高电压激活钙通道, 膜片钳

Abstract: The effects of cAMP and cGMP on the high-voltage activated (HVA) Ca2+ channels in the central neurons isolated from the 3rd instar larvae of the cotton bollworm (Helicoverpa armigera) were studied using the whole cell patch clamp technique. With barium as current carrier, the currents of Ca2+ channels were recorded by blocking Na+ and K+ currents. Extracellular application of 0.1 mmol/L forskolin, a stimulator of adenylyl cyclase (AC), had no effect on the peak amplitude of Ba2+ currents. In contrast, 1 mmol/L cGMP in the intracellular solution suppressed the current amplitude significantly and the inhibition was time and dose dependent. The results suggest that the activities of HVA Ca2+ channels in the cotton bollworm may not be affected by the elevated cAMP, but can be inhibited by the increased cGMP.

Key words: Helicoverpa armigera, cyclic AMP, cyclic GMP, high-voltage activated calcium channel, patch clamp