不同电针频率刺激对胃扩张疼痛大鼠下丘脑内P物质、β-内啡肽表达的影响  

Effect of Different Frequency Electroacupuncture on the Expression of Substance P andβ-endorphin in the Hypothalamus in Rats with Gastric Distension-induced Pain

作　　者：林亚平[1] 彭艳[1] 易受乡[1] 唐森[1] 李振海[1] 

机构地区：[1]湖南中医药大学针灸推拿学院,经穴与脏腑相关重点研究室,国家中医药管理局三级实验室,长沙410007

出　　处：《针刺研究》2009年第4期252-257,共6页Acupuncture Research

基　　金：国家重大基础研究(973)项目(2005-CB 523306-9);湖南省自然科学基金资助项目(06 JJ 50049);湖南省教育厅课题(08 C 632)

摘　　要：目的:通过比较不同电针频率刺激"足三里"对胃扩张疼痛大鼠的拟痛行为学评分和下丘脑内疼痛信息物质P物质(SP)、β-内啡肽(β-EP)的影响,阐明电针防治胃扩张疼痛可能的物质基础,探讨不同电针频率的效应差异。方法:50只大鼠完全随机分成空白组、假手术组、模型组、低频电针组和高频电针组,除空白组外采用胃内植入气囊并充气40mmHg压力造成胃扩张疼痛模型,低频(2Hz)和高频(100Hz)电针刺激"足三里"为施治因素,观察大鼠拟痛行为学评分,用免疫组化法检测下丘脑组织中SP、β-EP的表达。结果:低、高频电针均能明显降低胃扩张疼痛大鼠的拟疼痛行为学评分,与针前比较差异有统计学意义(P<0.01);且高频电针组优于低频电针组(P<0.01)。与空白组和假手术组比较,模型组下丘脑组织中SP、β-EP阳性细胞数明显增加(P<0.01),低、高频电针可使下丘脑组织中SP、β-EP阳性细胞数继续增加(P<0.01),且低频电针组的SP、β-EP阳性细胞数增加更明显(P<0.01)。结论:不同电针频率刺激"足三里"均可减轻胃扩张疼痛大鼠的应激反应,这可能是通过促进了下丘脑内疼痛信息物质SP、β-EP的合成与释放,从而发挥镇痛作用,且高频电针的镇痛效应优于低频针。Objective To observe the effect of different frequency electroacupuncture （EA） on hippocampal substance P （SP） and β-endorphin （β-EP） in rats with gastralgia so as to explore its underlying mechanism in preventing and relieving vis- ceral pain. Method Fifty rats were randomly divided into control, sham operation, model, low- frequency-EA and high frequen- cy-EA groups. Gastralgia model was duplicated by gastric distension （a pressure of 40 mmHg） with a latex balloon. Low （2 Hz） and high （100 Hz） frequency EA was applied to bilateral ＂Zusanli （ST 36）＂ for 30 min. Pain score was given by using Al-Ohaer＇s method （abdominal withdrawal reflex） and the expression of hypothalamic β-EP and SP was detected by immunohistochemistry. Results Both low- and high-frequency EA of ST 36 could significantly lower the pain score （P〈0.01 ）, and the effect of high- frequency EA was markedly superior to that of low-frequency （ P〈0.01 ）. Compared with control and sham-operation groups, both SP immuno-reaction （IR） and β-EP IR positive cells in the hypothalamus in model group increased significantly in the number （P〈0.01）, suggesting an upregulation of SP and β-EP expression after occurrence of gastralgia. In comparison with model group, the number of SP IR and #-EP IR positive cells in the hypothalamus in low frequency and high frequency EA groups in- creased further （P^0.01） particularly in low frequency EA group. Conclusion Both low-frequency and high-frequency EA of ＂Zusanli（ST 36）＂ can effectively relieve gastric distension-induced gastralgia in the rat, and the effect of high-frequency EA is better, which may be closely related to its actions in promoting the release and synthesis of hypothalamic β-EP and SP.

关 键 词：内脏痛 电针 低频 高频 下丘脑 Β-内啡肽 P物质 

分 类 号：R245.97[医药卫生—针灸推拿学]