缝隙连接对正常血压和自发性高血压大鼠肠系膜动脉收缩反应的影响

摘要

Objective To compare the contraction activities of mesenteric artery(MA) induced by KC1 and PE between normo tensive Wistar rats and spontaneously hypertensive rats(SHR) ,and to investigate the effects of gap junction on the vascular con traction activities. Methods Pressure myograph was used to observe the influences of KC1 and PE(endothelial independent vaso constrictor) on the vascular contraction activities,and the differences after applying 2-APB(gap junction blockers) in acute separa ted MA of Wistar rats and SHR. Results (1) KC1 and PE induced concentration dependently contraction reactions, and the con traction amplitudes induced by KC1 and PE was higher in SHR than Wistar rats respectively,there was significant difference(P＜ 0. 05). (2) After application 2-APB(100 μmol/L) ,the contraction amplitudes of mesenteric artery induced by KC1 and PE was obvi ously suppressed respectively(P＜0. 05) ,and more significantly in SHR(P＜0. 01). Conclusion the contraction reactions of mesen teric artery in SHR are higher than in Wistar rats through increasing the gap junction communication among smooth muscle cells of MA in SHR.%目的 本研究通过给予KCl和PE,观察正常血压Wistar大鼠和自发性高血压大鼠(SHR)肠系膜动脉(MA)收缩反应的异同,并探讨细胞间缝隙连接在血管收缩反应中的作用.方法 应用压力肌动图技术,在急性分离的Wistar大鼠和SHR的 MA 2级动脉分支上,观察内皮非依赖血管收缩剂KCl和PE对血管收缩的影响以及应用缝隙连接阻断剂2-APB后对血管收缩反应的影响.结果 (1) KCl和PE可以引起浓度依赖的收缩反应,且在SHR MA上KCl和PE引起的收缩幅度高于Wistar大鼠,差异有统计学意义(P<0.05).(2) 预灌流缝隙连接阻断剂 2-APB(100 μmol/L)后KCl和PE引起的血管收缩均显著降低(P<0.05),其中SHR降低幅度更加显著(P<0.01).结论 内皮非依赖收缩剂KCl和PE引起的SHR MA收缩幅度增强可能是通过增强血管平滑肌细胞间缝隙连接通讯增强介导.