辣椒素对大鼠骶髓后连合核神经元AMPA受体所介导电流的抑制作用  

Suppression of AMPA receptor-mediated currents by capsaicin in rat sacral dorsal commissural neurons

作　　者：屈波[1] 权毅[1] 潘显明[1] 邓少林[1] 洪桢[2] 王殿仕[2] 

机构地区：[1]成都军区总医院骨科,成都610083 [2]第四军医大学解剖学教研室暨梁銶琚脑研究中心,西安710032

出　　处：《中华神经医学杂志》2007年第9期909-913,共5页Chinese Journal of Neuromedicine

基　　金：国家自然科学基金(30300077)

摘　　要：目的研究辣椒素(CAP)在急性分离的大鼠骶髓后连合核(SDCN)神经元的药理学特性。方法采用制霉菌素穿孔膜片钳全细胞记录方法。结果当钳制电压为-40 mV时,在所有被检测的SDCN神经元上给予CAP不引起任何电流;CAP(10～3 000μmol/L)可以呈浓度依赖方式可逆性的抑制海人藻酸(KA)所激活的AMPA受体介导的电流,IC_(50)为(60.7±19.2)μmol/L;该抑制作用呈电压非依赖性。结论CAP在大鼠SDCN神经元可对AMPA受体激活的电流产生抑制作用,此作用可能和内脏痛的调节有关。Objective To investigate the effect of capsaicin （CAP） on kainate （KA）-evoked responses in neurons acutely dissociated from the rat sacral dorsal commissural nucleus （SDCN）. Methods Nystatin-perforated patch-recording configuration under voltage-clamp conditions was employed. Results The responses to KA were mediated by the activation of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid （AMPA） receptors in SDCN neurons. CAP reversibly inhibited KA （100 μmol/L）-activated currents （IKA） in a concentration-dependent manner over the concentration range of 10 μmol/L to 3 000 μmol/L with the IC50 value of （60.7±19.2） μmol/L at a holding potential of-40 mV. Our further study indicated that the effects of CAP on IKA were voltage-independent. Moreover, the inhibition was not use-dependent and not overcomed by increasing the concentration of agonist. Conclusion CAP is an efficacious inhibitor of AMPA receptor-mediated responses, which may contribute to the modulation of visceral pain.

关 键 词：辣椒素 AMPA受体 骶髓后连合核 海人藻酸 制霉菌素穿孔膜片钳 

分 类 号：R285[医药卫生—中药学]