豚鼠尿道Cajal间质细胞在交感神经诱发平滑肌收缩中的作用研究

Role of interstitial cells of Cajal of guinea pig urethra in contraction of smooth muscle induced by sympathetic nerve

目的:探索豚鼠尿道Cajal间质细胞(ICC)在交感神经诱发平滑肌收缩中的作用。方法:(1)制作豚鼠尿道组织切片并进行免疫荧光双染,使用酪氨酸激酶受体(c-Kit)抗体标记ICC,多巴胺β羟化酶标记交感神经,!-actin标记平滑肌细胞。分别使用c-Kit、α1-肾上腺受体抗体和cKit、Cx-43抗体进行免疫荧光双染。(2)将尿道肌条固定于灌流槽中,记录交感神经递质去甲肾上腺素诱发肌条收缩的频率和幅度,加用Glivec后记录肌条收缩的频率和幅度变化。结果:(1)免疫荧光双染标记发现豚鼠尿道ICC和交感神经、平滑肌细胞之间具有密切的形态学联系。ICC细胞膜上表达α1-肾上腺受体和缝隙连接蛋白Cx-43。(2)体外肌条实验结果:去甲肾上腺素诱发尿道肌条收缩幅度为(1.26±0.15)g,收缩频率为(2.55±0.27)min-1;使用50、200μmol/L Glivec抑制ICC功能后尿道肌条的收缩幅度为(0.85±0.11)g、(0.38±0.07)g。使用50、200μmol/L Glivec抑制ICC功能后尿道肌条的收缩频率为(2.52±0.19)min-1、(2.66±0.29)min-1。Glivec明显降低了尿道肌条收缩的幅度(P<0.01),但对收缩的频率未产生显著影响(P>0.05)。结论:豚鼠尿道ICC具有介导交感神经信号,调控平滑肌活动的形态和功能学基础。

Objective:To explore the role of interstitial cells of Cajal(ICC)in smooth muscle contraction induced by sympathetic nerve in guinea pig urethra.Methods:①The guinea pig urethra slices were made for double-labeling immunofluorescence.c-Kit was used to mark ICC,the dopamineβ-hydroxylase was used to mark sympathetic nerve,andα-actin was used to mark smooth muscle cells.Double-labeling immunofluorescence was performed using c-Kit,α1-adrenergic receptor antibody,c-Kit and gap junction protein Cx-43 antibody respectively.②The guinea pig urethral muscle strips were fixed in the perfusion slot,and the frequency and amplitude of the contraction of the urethral muscle strips induced by the norepinephrine(NE)were recorded before and after the presence of Glivec.Results:①Immunofluorescence showed that there was close morphological relationship between ICC and sympathetic nerve and smooth muscle cells in guinea pig urethra.α1-adrenoceptor and Cx-43 were coexpressed in ICC.②The amplitude of NE induced contraction of urethral strips was(1.26±0.15)g and the frequency was(2.55±0.27)min-1.The contraction amplitude of the urethral strips after applicationof 50μmol/L Glivec and 200μmol/L Glivec was(0.85±0.11)g and(0.38±0.07)g respectively.The frequency after applicationof 50μmol/L Glivec and 200μmol/L Glivec was(2.52±0.19)min-1 and(2.66±0.29)min-1.Glivec significantly decreased the contraction amplitude of urethral strips(P<0.01),but did not affect the contraction frequency(P>0.05).Conclusion:ICC in guinea pig urethra has the morphological and functional foundation which involved in mediating sympathetic signal and regulating the activity of smooth muscle.