目的探讨肾叶间动脉(RIA)的缝隙连接(GJ)在自发性高血压病中的变化。方法应用压力肌动图技术观察自发性高血压大鼠(SHR)及Wistar大鼠RIA对内皮非依赖血管收缩剂氯化钾(KCl)和苯肾上腺素(PE)的收缩反应的差异,以及应用GJ阻断剂后血管收缩反应的变化。应用Western blot技术比较SHR及Wistar大鼠RIA连接蛋白45(Cx45)的表达差异。结果 1 KCl和PE诱导SHR RIA的收缩反应要强于Wistar大鼠,应用GJ阻断剂18β-甘草次酸(18β-GA)(100μmol/L)干预后,KCl和PE引起的RIA血管的收缩明显降低,SHR较Wistar大鼠收缩降低幅度更为显著。2 SHR大鼠RIA Cx45蛋白表达升高(P〈0.05)。结论SHR RIA收缩作用的增强可能是通过上调Cx45增强平滑肌细胞间GJ通讯引起的。
Objective To investigate the change of gap junction in renal interlobar of spontaneous hypertension rats (SHR) and its relationship with hypertension. KC1 and phenylephrine (PE) on the vascular Methods Pressure myograph was used to observe the influences of contraction activities, and the differences after applying 18β-GA in RIA of SHR and Wistar rats. Western blot technique was used to investigate the differences in expressions of con- nexin 45 ( Cx45 ) on protein levels in renal interlobar artery between SHR( n = 20) and Wistar rats ( n = 20). Re-sults①The contraction reaction was induced by KC1 and PE in a concentration dependent manner, and the con-traction reaction of SHR was stronger than Wistar rats. After applying of 18β-GA ( 100 μmol/L) , KC1 and PE caused the significantly lower contraction rate of RIA, and that was more significant in SHR. ② The expression of Cx45 protein was significantly elevated in renal interlobar artery from SHR compared with normotensive Wistar rats (P 〈 0. 05 ). Conclusion The enhancement of contraction of RIA in SHR maybe relate to the upregulation of Cx45 expression and increase gap junction communication in vascular smooth muscle cells of renal interlobar artery from SHR.