家福捕鸟蛛粗毒对DRG细胞上电压门控离子通道的影响

Effects of Venoms from the Sqider Selenocosmia Jiafu on Voltage- gated Ion Channels in Rat Dorsal Root Ganglion Neurons

采用全细胞膜片钳分析,测定了家福捕鸟蛛粗毒对DRG细胞上电压门控钠、钾和钙离子通道的影响.结果表明:粗毒对大鼠背根神经节(dorsal root ganglion,DRG)细胞上河豚毒素敏感型钠通道、河豚毒素不敏感型钠通道、电压门控钾通道、高电压激活钙通道和低电压激活钙通道都具有抑制作用.100μg/m L的粗毒分别能够抑制64.0%河豚毒素敏感型钠电流、46.5%河豚毒素不敏感型钠电流、44.2%电压门控钾电流和77.7%低电压激活的钙电流.50μg/m L的粗毒能够抑制大约74.9%高电压激活的钙电流.结果表明家福捕鸟蛛粗毒中可能存在开发为新型药物和离子通道工具试剂的毒素分子.

Selenocosmia jiafuis recently identified new species of spider in P. R. China. These medium bodied venomous spiders are distributed mainly in the hilly areas of southwest of China,mostly in Yunnan and Guangxi Province.The venom of this spider contains many components with different biological activities. In order to explore the utility of this rich source,researchers observed the effects of the venoms from the spider Selenocosmia jiafu on voltage- gated ion Na~＋,K＋and Ca^（2 ＋） channels in rat dorsal root ganglion neurons by voltage- clamp analysis. The venom could inhibit tetrodotoxin- sensitive sodium channels,tetrodotoxin- resistant sodium channels,voltage- gated potassium channel,high- voltage-activated calcium channels and low voltage- activated calcium channels in rat DRG neurons as revealed by voltage- clamp analysis. Crude venom at concentration of 100 μg / m L could inhibit 64. 0% ± 6. 2% tetrodotoxin- sensitive sodium current,46. 5% ± 3. 8% tetrodotoxin- insensitive sodium current,44. 2% ± 5. 3% voltage- gated potassium currents and 77. 7% ±9. 9% low- voltage- activated calcium currents. At a concentration of 50 μg / m L,the venom could inhibit approximately 74. 9% ± 2. 8% of high voltage- activated calcium currents. It suggested that the venom might contain various channel antagonists,which could become candidates for valuable tools for investigation of ion channels and drug development.