电针对慢性炎症疼痛大鼠背根神经节牛肾上腺髓质22肽及其受体基因表达的影响

Effects of Electroacupuncture on Bovine Adrenal Medulla 22 and mRNA Expression of its Receptors in Lumbar Dorsal Root Ganglion in Rats with Chronic Inflammatory Pain

[目的]观察电针对完全福氏佐剂(complete freund’s adjuvant,CFA)致慢性疼痛大鼠患侧腰背根神经节(dorsal root ganglion,DRG)牛肾上腺髓质22肽(BAM22)与其感觉神经元特异性受体(SNSR)、MOR与DOR基因表达的影响。[方法]200±20g雄性SD大鼠30只,随机分成正常对照组、模型对照组、电针组,每组10只,模型对照组、电针组右足CFA造模。电针组从造模24h开始治疗,患侧"足三里"穴,2/100Hz,30min,1次/d,治疗10d,其余2组不予治疗。采用辐射热法检测大鼠缩爪潜伏期观察大鼠患侧热痛敏变化,免疫组化法检测患侧背根神经节BAM22多肽的含量,定量PCR(quantitative polymerase chain reaction,qPCR)法检测患侧背根神经节SNSR、MOR与DOR mRNA的表达。[结果]经过10d的治疗,电针组的痛阈与模型对照组相比,有显著提高(P<0.05)。免疫组化结果显示,电针干预后,患侧背根神经节的BAM22阳性细胞率比模型对照组有显著的提高(P<0.01)。定量PCR结果显示,电针极大地促进了SNSR(P<0.01)、MOR(P<0.01)与DOR mRNA(P<0.01)在患侧DRG中的表达。[结论]电针对CFA大鼠慢性疼痛有良好的干预作用,推测该作用与电针增强患侧腰背根神经节BAM22多肽表达,增强其非阿片受体SNSR与其阿片受体MOR与DOR mRNA表达相关。

[Objective] To observe the effects of electroacupuncture（EA） on expression of bovine adrenal medulla 22（BAM22） and gene expression of its senso- ry neuron-speciic receptor（SNSR）, MOR and DOR receptors in lumbar dorsal root ganglion（DRG） in rats with complete Freund＇s adjuvant（CFA）-in- duced chronic in ammatory pain.[Methods] Thirty male SD rats were randomly selected as normal group, model group and EA group,with 10 in each . Model group and EA group were made chronic in ammatory pain induced with CFA. Modeled after 24h, the EA group were treated with 2/100Hz EA in control Zusanli（ST36）,30 min each time,once per day, for 10 days, while no treatment was given to other groups. The control thermal pain threshold as an index of therapeutic effect was observed by deceting paw with-drawal latency（PWL）, and expressions of BAM22 in the affected side DRG by immuno- histochemical staining, gene expressions of SNSR, MOR and DOR in DRG by real-time fluorescence quantitative PCR were detected.[Results] Compared with model group, ten-day EA obviously raised the pain threshold of EA group. The ratio of cells in the affected side DRG expressing BAM22 was significantly increased（P〈0.01）, and the mRNA amount of SNSR MOR, and DOR（P〈0.01） of EA group in the affected side DRG were also remark- ably increased. [Conclusions] EA can get analgesia effect on CFA-induced chronic in ammatory pain, and the effect is closely associated with up-regulating the expressions of BAM22 and the mRNA expressions of its receptors： SNSR, MOR and DOR in affected side DRG.