急进高原胃动力紊乱大鼠胃电起搏区Cajal间质细胞和缝隙连接蛋白43的表达

摘要

Objective To investigate the gastric pacing interstitial cells of Cajal(interstitial cell of Cajal,ICC)and Connexin43( Cx43) expression in rats after ascending to high altitude, and to explore its mechanism. Methods Thirty SD male rats were divided into three groups(n=10 in each group):low altitude group (Xi’an, 400 m), high altitude(4 300 m) 3 d, 14 d groups. The rats’ gastric electrical activity was measured in different groups. Electron microscope was applied to observe the physiological ultrastructure of ICC cells, and the immunofluorescence staining was used to observe the expression of ICC cells and Cx43 in gastric electrical pacing region. Results The amplitude and frequency of gastric electrical activity of rats were the lowest in high altitude 3 d group ( P<0. 05). The gap junctions and organelles of ICC cells were reduced in high altitude 3 d group, and the apoptotic bodies were observed by electron microscope. The expression of ICC cells and Cx43 was also the lowest in high altitude 3 d group(P<0. 05). Conclusion The damages of ICCs,Cx43 abnormal expression, and the destruction of the gap junction may induce the dysfunctions of intercellular substance exchange and signal transmission,which might partly be responsible for the pathogenesis of gastric motility disorders in high altitude-exposed rats.%目的：通过观察急进高原大鼠胃动力紊乱发生过程中胃电起搏区Cajal间质细胞( interstitial cell of Cajal,ICC)与缝隙连接蛋白43(Connexin43,Cx43)的表达变化,探讨其机制。方法30只SD大鼠以低海拔地区(海拔400 m)为对照组,并以进入高原地区(海拔4300 m)后的时间节点分为3 d和14 d组,每组10只。测定各组大鼠胃电活动数据,电子显微镜观察胃电起搏区ICC的微观结构变化,双重免疫荧光组化法观察同区域ICC与Cx43的表达变化。结果急进高原后大鼠胃电活动的明显受损,波幅衰减尤以3 d显著(P<0.05),ICC的微观结构出现明显损伤,缝隙连接变得明显稀疏、松散。双重免疫荧光组织化学染色结果发现,Cx43及ICC细胞的表达于高原3 d明显减低(P<0.05),正常生理功能受损。结论 ICC细胞受损及其缝隙连接蛋白Cx43的表达异常导致平滑肌运动障碍,可能是胃动力紊乱发生的作用机制之一。