人食管下括约肌毒蕈碱受体的表达

Expression of muscarinic receptor subtypes in human lower esophageal sphincter

目的:研究毒蕈碱受体亚型在人食管下括约肌(LES)套索纤维和钩状纤维的表达,对LES胆碱能收缩机制作进一步分析.方法:选取高位食管中段癌,行食管大部切除术患者12例,取食管胃接合部标本分离套索纤维和钩状纤维.分别应用逆转录聚合酶链反应(RT-PCR)和蛋白印记(Western Blot)检测5种M受体亚型在两种肌纤维中mRNA和蛋白的表达.结果:不同M受体亚型mRNA在两种肌纤维的表达有统计学差异(P<0.05),从数据观察5种受体亚型mRNA表达从强到弱顺序依次为M2,M3,M1,M4,M5;同一受体mRNA在两种肌纤维间表达无统计学差异;不同M受体亚型蛋白在两种肌纤维表达有统计学差异(P<0.05),5种受体亚型蛋白表达强弱同mRNA;同一受体在两种肌纤维间蛋白表达无差异.结论:5种M受体亚型mRNA和蛋白在两种肌纤维均有表达,M2受体表达量最高,其它依次是M3,M1,M4和M5受体;相同受体在两种肌纤维间mRNA和蛋白的表达相同.

AIM： To explore the expression of mRNA and protein of muscrinic receptor subtybes in sling and clasp fibers of human lower esophageal sphincter （ LES ）. METHODS ： Smooth muscles strips of the sling and clasp fibers were obtained from 12 patients who underwent subtotal csophagectomy for middle thoracic esophageal carcinoma. RT-PCR and Western Blot were used to detect the expression of mRNA and protein of muscrinic receptor subtybes in sling and clasp fibers. RESULTS： Significant differences were demonstrated when comparing the expression of mRNA between muscrinic receptor subtybes in each muscle strip （P 〈 0.05）. The rank order of expression extent was M2, M3, M1, M4 and M5 receptor. However, there was no significant difference between both muscle fibers （ P 〉 0.05 ）. There was significant difference in the expression of protein between the five muscrinic receptor subtybes in same muscle strip （P 〈 0.05 ）. The rank order of the value of western Blot was the same as the result of RTPCR. There was no significant difference between the muscle fibers （P 〉 0.05 ）. CONCLUSION： Protein and mRNA of the five mAChRs are all detected in both muscle fibers. M2 expresses most strongly,followed by M3, M1, M4, and M5 in sequence. The mRNA and protein expression of the same muscrinic receptor shows no difference between the two muscle fibers.