转化生长因子β蛋白在气道重构哮喘豚鼠模型的表达及电针干预效应

Effect of electroacupuncture on the protein expression of transforming growth factor-beta in the airway of asthmatic Guinea pigs with airway remodeling

目的:通过卵清蛋白注射液制作气道重构哮喘豚鼠模型,观察气道转化生长因子β1蛋白表达及电针对其的影响。方法:实验于2005-08/10在广州中医药大学实验动物中心完成。选用健康豚鼠48只,雌雄各半。将动物按随机数字表法分为正常对照组、电针治疗组、地塞米松组和模型组4组,每组12只。电针治疗组,地塞米松组和模型组动物于实验第1天腹腔注射100g/L卵清蛋白注射液1mL以致敏,正常对照组动物腹腔注射0.9%生理盐水1mL。第15天起作部动物隔天用卵蛋白粉末加上生理盐水配成10g/L卵蛋白溶液超声雾化吸入约20s。电针治疗组每次卵白蛋白喷雾攻击前0.5h开始电针治疗。地塞米松组于每次卵白蛋白喷雾攻击前0.5h腹腔注射100g/L地塞米松1mL。正常对照组和模型组不进行干预。治疗结束后,采用免疫组织化学法检测与气道重构相关的细胞因子转化生长因子β1在各组动物支气管和肺组织中的蛋白表达。结果:纳入的48只豚鼠,4只于造模过程中死亡而脱落,其余44只进入结果分析。各组豚鼠的支气管、肺组织切片中均见棕黄色颗粒状的免疫阳性反应,主要集中在气道上皮细胞、基底膜、肺间质、软骨和炎症细胞中。模型组转化生长因子β1阳性细胞数明显高于对照组,差异有显著性意义(P<0.01);电针治疗组与地塞米松组的支气管肺组织转化生长因子β1阳性细胞数低于模型组,差异有显著性意义(P<0.05)。结论:①哮喘豚鼠气道重构模型气道转化生长因子β1的蛋白表达增加,电针豚鼠背六穴能降低气道重构豚鼠模型支气管肺组织中的转化生长因子β1蛋白表达。②电针豚鼠背六穴可通过下调转化生长因子β1蛋白表达干预哮喘豚鼠的气道重构。

AIM： To observe the protein expression of transforming growth factor-beta1 （TGF-β1） in the airway of asthmatic Guinea pigs with airway remodeling and to evaluate the effect of electroacupuncture （EA） on the expression. METHODS： The experiment was performed in the Experimental Animal Center of Guangzou University of Traditional Chinese Medicine from August to October 2005. Forty-eight healthy Guinea pigs were selected with half mate and half female. They were randomly divided into normal control group, EA group, dexamethasone group and model group with 12 animals in each group. Except the control group [1 mL normal saline （0.9%）], all Guinea pigs were intraperitoneally injected with 1 mL ovalbumin （100 g/L） at the first day and given nebulized inhalation of 10 g/L ovalbumin solution with normal saline at the 15^th day for about 20 seconds. The animals in EA group were given electroacupuntur, and in dexamethasone group were given 1 mL dexamethasone injection （100 g/L） 0.5 hour before nebulized inhalation. But normal control group and model group were not given any treatment. After treatment, the protein expression of TGF-β1 in bronchi and lung was detected by immunohistochemical method. RESULTS： Of the 48 Guinea pigs, 44 were finally involved in the result analysis, because 4 died of remodeling. Immune positive response of yellow granules was found in bronchi and lung samples, mainly distributing at epithelial cells of airway, basal membrane, interstitial substance, cartilage and inflammatory cells. The positive cell number of TGF-β1 in model group was significantly higher than normal control group （P 〈 0.01）, and in dexamethasone group and EA group was significantly lower than model group （P 〈 0.05）. CONCLUSION： （1）Protein expression of TGF-β1 is increased in the airway of asthmatic Guinea pigs with airway remodeling, and EA of back six points （Dazhu, Fengmen, Feishu） can decrease the protein expression of TGF-β1. （2） The therapeutic mechanism of EA of back six points for airway remodeling is related to the downregulation of TGF-β1 protein expression.