低频电针降低神经病理痛大鼠背根神经节p-CREB的表达

Low Frequency Electroacupuncture Decreasing p-CREB Expression in Dorsal Root Ganglia of Rats with Neuropathological Pain

目的：观察低频脉冲电针对慢性神经病理痛大鼠背根神经节磷酸化环磷酸腺苷反应元件结合蛋白（p-CREB）表达的影响。方法：36只成年雄性SD大鼠,随机分为空白对照组、假手术组、模型对照组和电针治疗组,每组9只。模型对照组和电针治疗组采用右侧慢性坐骨神经结扎的方法,建立慢性神经病理痛模型。电针组大鼠给予低频电针刺激双侧＂夹脊＂穴和＂足三里＂穴,参数为波宽0.6 m s,频率2 Hz,电流强度分别为0.5、1和2 mA,各10 m in,共刺激30 m in。空白对照组、假手术组和模型对照组只陪同电针组抓取、固定,不做任何治疗。使用免疫印迹方法,观察各组大鼠右侧L4-6背根神经节p-CREB的表达变化。结果：模型对照组的热痛阈较空白对照组显著降低,并伴见p-CREB表达的显著增高（P〈0.01）。电针治疗组的热痛阈和p-CREB表达,较模型对照组均有显著变化（P〈0.05）。结论：低频脉冲电针的镇痛作用可能部分是通过抑制p-CREB的表达实现。电针可以通过改变初级传入神经元中基因的表达而对疼痛起到调控作用。

Objective: to observe the effect of pulse electroacupuncture with low frequency on p-CREB expression in dorsal root ganglia of rats with chronic neuropathological pain.Methods: 36 SD rats were randomly divided into control group,sham operation group,model group and electroacupuncture group.Model group and electroacupuncture group were made by chronic sciatic nerve ligation on right side.The electroacupuncture group were given low frequency stimulation in bilateral Jiaji(EX-B 2) and Zusanli(ST 36) with wave width 0.6 ms,frequency 2 Hz,current strength 0.5 mA,1 mA and 2 mA for 10 minutes each and totally 30 minutes,while the other were caught and fixed without any treatment.Immunoblotting was employed to observe the p-CREB expression changes in dorsal root ganglia L4-6.Results: thermalgia threshold of model group was obviously lower than control group,accompanied with p-CREB significantly increasing(P<0.01).Thermalgia threshold and p-CREB expression of treatment group were significantly different from those of control group(P<0.05).Conclusion: low frequency pulse electroacupuncture can relieve pain partly by inhibiting p-CREB expression,and regulate pain by changing the genetic expression in primary afferent neurons.