吗啡处理对大鼠延髓头端腹内侧区的L-型电压门控钙通道蛋白与电流的影响

Effects of Morphine Treatment on the Protein Levels and Currents of L-type Voltage-gated Calcium Channels in the Rostral Ventromedial Medulla of Rats

【目的】探讨在吗啡引起的痛觉超敏状态下,SD大鼠延髓头端腹内侧区电压门控钙通道（voltage-gated calcium channels, VGCCs）蛋白的表达变化和功能变化。【方法】采用western blot方法检测α1C和α1H亚基蛋白在大鼠延髓头端腹内侧区（the rostral ventromedial medulla,RVM）的表达,采用脑片全细胞膜片钳技术记录大鼠RVM神经元的VGCCs电流。【结果】在吗啡诱导的痛觉超敏状态下,SD大鼠RVM的α1C亚单位蛋白表达显著增加,同时神经元的VGCCs总电流和L-型VGCCs电流也显著增加。【结论】延髓RVM的L-型电压门控钙通道的可塑性变化,可能是导致吗啡痛觉超敏的重要原因。

【Objective】To investigate the changes of voltage-gated calcium channels （VGCCs） in the rostral ventromedial medulla of SD rats under morphine-induced hyperalgesia. 【Methods】The expression of a1C and a1H subunit proteins in the rostral ventromedial medulla （RVM） was detected by western blot. The VGCCs current of RVM neurons was recorded by the whole-cell patch-clamp technique. 【Results】Our results indicated that the expression of α1C subunit in the RVM significantly increased under morphine-induced hyperalgesia, which was followed by the significant increase in total VGCCs currents and L-type VGCCs currents. 【Conclusion】This data implicates that α1C-subunit-containing L-type VGCCs in RVM may play an essential role as a cellular mechanism leading to hyperalgesia.