胃牵涉皮区不同频率电刺激对大鼠胃痛及相关神经元c-fos表达的影响

EFFECTS OF FREQUENCY DEPENDENT ELECTRICAL STIMULATION ON STOMACHACHE AND C-FOS EXPRESSION IN RATS

目的:为临床经牵涉区实施简便易行无创的电刺激缓解胃痛及阐释牵涉痛机制的提供实验依据。方法:(1)实验用SD大鼠,以定量10%Formalin灌胃法建立胃痛模型,经尾静脉注射伊文思蓝,以胃痛大鼠体表"渗漏斑"所在局部作为胃痛牵涉区;(2)用韩式仪以2 Hz、100 Hz、2/100 Hz交替等不同频率和方式,经胃痛牵涉区施加电刺激,观测各实验组大鼠不同时间点的疼痛行为学改变后,进一步用免疫组化法和免疫印迹法测试脑和脊髓等部位的c-fos表达,统计分析各因素的相关性。结果:正常大鼠体表未见明显伊文思蓝渗漏斑,胃痛大鼠在其肩胛间区见有明显渗漏斑;经该渗漏斑所在部位给胃痛大鼠不同频率和方式电刺激后,以2/100 Hz交替电刺激组疼痛行为学评分最低,且其相关部位c-fos表达最少,与其他各组相比,P<0.001。结论:大鼠胃痛牵涉区位于肩胛间区。经此区给予胃痛大鼠2/100 Hz交替电刺激可明显缓解胃痛,且与胃运动与感觉相关部位神经元Fos蛋白等信号物质表达量呈正相关。本研究为临床经牵涉区实施简便易行无创的电刺激缓解胃痛以及阐释牵涉痛发生机制的提供了科学的实验依据。

Objective： To provide the experimental basis for the simple and noninvasive electric stimulation to relieve stomachache and the mechanism of stomachache referred pain. Methods： （1） In this experiment, the SD rats were given intragastric administration with 10% formalin, to establish the stomachache model. Evans blue was injected into SD rats＇ tails vein, the ＂leakage spots＂ in the body surface area was regarded as the stomachache referred area; （2） Applying electrical stimulation in the stomachache referred area with different fi＇equencies such as 2 Hz, 100 Hz and 2/100 Hz using HANS, afterwards, we observed SD rats＇ changes of pain-related behavior at some specific points in time, the expression of c-los of referred areas were detected further by immunohistochemical and western blot, at last, we analyzed the correlation of various factors. Results： The leakage spots of Evans blue were not detected at normal rats. However, obvious spots were seen at shoulder blades of rats suffered ~om stomachache. After electrical stimulation at referred area, the pain scores and c-los expression were the lowest in 2/100 Hz group, compared with other groups （P 〈 0.001）. Conclusion： The rat＇s skin referred area of stomachache was located in shoulder blades. The 2/100 Hz electric stimulation at the referred area can relieve rats＇ stomachache. There are positive correlation between its effect and the expression of signaling molecules such as c-los related to particular gastric motor and sensory neurons. This experiment provides the experimental basis for the simple and noninvasive electric stimulation to relieve stomachache and the mechanism of stomachache referred pain.