不同参数电针对大鼠脊髓背角神经元伤害感受性反应的影响

Effect of electro-acupuncture with various parameters on the nociceptive response of spinal cord dorsal horn neurons in the rat

目的 观察和比较不同参数电针对大鼠“足三里穴”的镇痛效应。方法 采用玻璃微电极细胞外记录大鼠腰部脊髓背角广动力型 (WDR)和特异伤害感受型 (NS)神经元的活动 ,观察了不同强度 (1mA ,5～ 6mA)和不同频率 (5、2 0、5 0、10 0Hz)电针对背角神经元伤害感受性反应 (C 反应 )的影响。结果 强电针时选用低频 (5Hz)较好 ,而弱电针时选用高频 (5 0Hz)为佳。

Objective To observe and compare the analgesic effects of electro-acupuncture(EA)of “Tsusanli point” (St. 36) with various stimulation parameters. Methods Single wide dynamic range (WDR) and nociceptive specific (NS) neurons were recorded extracellularly in the dorsal horn of the rat lumbar spinal cord. The late train discharges (C-response) of the neurons evoked by intense electrical stimulation of the skin were used as a nocicepive response. The inhibitory effects of EA stimulation of the “Tsusanli point” (St. 36) with various intensities (1 and 6 mA) and frequencies (5, 20, 50 and 100 Hz) on the C-response were observed, respectively. Results A lower frequency (5 Hz) was appropriate to the high-intensity EA, while a higher frequency (50 Hz) was proper for the low-intensity EA. Conclusion The effect of EA on the spinal nociceptive transmission is both intensity- and frequency-dependent.