β肾上腺素受体在豚鼠输尿管ICC细胞上的表达及功能研究

Expression of β-adrenoceptor in interstitial cells of Cajal of guinea-pig ureters and its function

目的研究β肾上腺素受体在豚鼠输尿管ICC细胞上的表达及意义。方法通过离体肌条实验,观察对照组(正常豚鼠肌条)和实验组(Glivec选择性阻断ICC细胞的肌条)在β肾上腺素激动剂作用下输尿管肌条的收缩幅度和频率的变化;采用免疫荧光双标技术检测豚鼠输尿管β肾上腺素受体亚型(β1、β2和β3)在ICC细胞上的表达情况。结果非选择性β肾上腺素激动剂(异丙肾上腺素)作用后,对照组的收缩幅度[(0.070±0.035)g]较实验组的幅度[(0.100±0.028)g]下降显著(P<0.05),频率[(2.480±1.210)/min]较实验组的频率[(7.200±3.580)/min]下降亦显著(P<0.01),实验组在异丙肾上腺素作用下的舒张效应不如对照组显著;免疫荧光双标显示,输尿管ICC细胞仅表达β3受体亚型;选择性β3肾上腺素激动剂(CGP12177)作用后,对照组的收缩幅度[(0.068±0.023)g]和频率[(3.870±0.474)/min]较实验组的幅度[(0.115±0.031)g]和频率[(6.410±1.895)/min]均下降显著(P<0.05),实验组在CGP12177作用下的舒张效应不如对照组显著。结论去甲肾上腺素能神经可能通过激活ICC细胞上的肾上腺素β3受体来调节输尿管收缩与舒张。

Objective To study the expression of β-adrenoceptor in interstitial cells of Cajal（ICC） of guinea-pig ureters and its function.Methods Guinea pigs were divided into control group and experimental group.Changes in ureteral muscle contraction amplitude and frequency of ureteral muscle contraction after treatment with β-adrenergic agonist,were observed.Expression of β-adrenergic receptor subtypes（β1,β2 and β3） in ICC of guinea-pig ureters was detected using immunofluorescence double labeling technique.Results After treatment with isoprenaline,the ureteral muscle contraction amplitude and the frequency of ureteral muscle contraction were significantly lower in control than in experimental group（0.070 ± 0.035 vs 0.100 ± 0.028,7.200 ± 3.580 vs 2.480 ± 1.21,P 0.05）,indicating that the relaxing action of isoprenaline on ureteral muscle was greater in control group than in experimental group.Immunofluorescence double labeling showed that β3 receptor subtypes were expressed only in ureteral ICC.After treatment with selective β3-adrenergic agonist（CGP12177）,the ureteral muscle contraction amplitude and the frequency of ureteral muscle contraction were significantly lower in control group than in experimental group（0.068 ± 0.023 vs 0.115 ± 0.031,3.870 ± 0.474 vs 6.410 ± 1.895,P 0.05）,showing that the relaxing action of CGP12177 on ureteral muscle was weaker in experimental group than in control.Conclusion Noradrenergic nerves can regulate the ureter contraction and relaxation by activating the β3 adrenergic receptor subtypes of ICC.