中文摘要：

目的：观察不同pH值的Kreb＇s液对人食管下段平滑肌条的体外收缩功能的影响,同时明确食管环形肌（circular smoothmuscle,CM）及食管纵行肌（longitude smooth muscle,LM）对其反应的区别,以探讨酸性反流性食管炎及Barrett食管的相关发病机制。方法：根据24h食管pH值检测、食管镜检及HE染色结果,分辨、筛选正常人食管平滑肌,制备环形平滑肌与纵行平滑肌条,描述4种pH值Kreb＇s液（pH：6.7,6.9,7.1,7.3）组给药前后人食管肌条收缩曲线。结果：LM在各组pH条件下乙酰胆碱的浓度依赖收缩反应无明显差异,但是CM在pH为6.7组中收缩反应明显低于其他各组;LM在各pH组中对异丙肾上腺素舒张反应无明显差异,而CM在pH为6.7及6.9组异丙肾上腺素舒张反应明显降低。结论：不同的酸性条件下食管平滑肌中的纵行肌及环行肌对乙酰胆碱及异丙肾上腺素的反应性不同,酸损伤减弱CM收缩及舒张反应,可能参与反流性食管炎、Barrett食管等食管运动功能性疾病的发生过程。

英文摘要：

Objective： To observe contractile and relaxation function of the lower esophageal smooth muscle strips in the next paragraph at different pH value, a series of experiments was designed in this study. The difference of effort between human esophageal longitude smooth muscle （LM）and circular smooth muscle （CM） was detected. Methods： Normal esophageal smooth muscle strips was selected according to the 2411 esophageal pH testing, esophageal endoscopy, and HE staining. Contraction curve of human esophageal muscle strips was drawn under 4 different pH solution： 6.7, 6.9, 7.1, 7.3. Results： The pH of the Kreb＇s solution has no effect on concentr ation-dependent contracting response to acetylcholine （Ach） in the LM, but responses obtained in pH 6.7 solution were significantly lower in CM （P〈0.05）. In pH 6.7 and 6.9 solution, concentration-dependent relaxation responses to isoproterenol were also sianificantly lower （P〈0.05）. Conclusions： Although the esophageal longitude smooth muscle had no differences in response to acetylcholine and isoproterenol stimulation caused by different pH solution, the responses of CM were lower in acidic pH solution. The acid damage of circular smooth muscle may contribute to the gastroesophageal reflux disease.