自发性高血压大鼠肾脏和胰腺微循环血流灌注和自律运动变化

Renal and Pancreatic Microcirculatory Blood Perfusion and Vasomotion in Spontaneously Hypertensive Rats

目的:观察自发性高血压大鼠(SHRs)肾脏和胰腺微循环血流灌注和自律运动变化。方法:市购8周龄SHRs(SHR组)和正常血压对照大鼠(WKY组)各6只,手术暴露肾脏和胰腺。采用双通道激光多普勒血流仪,多点观测其表面的微血流灌注和自律运动水平,并通过仪器自带分析软件的小波变换功能将微血流信号转换为二维频谱图和三维时频图像,比较两组大鼠肾脏、胰腺血流灌注水平、血流速度和血细胞浓度的变化特征及微血流灌注频谱中一氧化氮(NO)依赖与否的内皮细胞源频段幅值差异。结果:与WKY组相比,SHR组肾脏、胰腺微血流灌注水平均显著降低(P<0.05或P<0.01);同时呈现胰腺微血管自律运动节律紊乱。SHR组肾脏和胰腺微血管自律运动振幅和频率均显著降低(P<0.05或P<0.01)。SHR组肾脏和胰腺微血流灌注频谱中NO依赖与否的内皮细胞源频段振幅均显著低于WKY组(P<0.05或P<0.01)。结论:SHRs肾脏、胰腺微循环功能异常,表现为微血流灌注水平下降,微血管自律运动功能障碍。

Objective:To investigate the changes of renal and pancreatic microcirculatory blood perfusion and vasomotion in spontaneously hypertensive rats(SHRs).Method:8-week-old SHRs(SHR group)and normotensive control Wistar Kyoto rats(WKY group)were selected(n=6 each group).After exposing kidney and pancreas,multi-point microcirculatory blood perfusion and vasomotion on the surface of organs were determined by dual-channel laser Doppler blood perfusion monitoring system.Wavelet transform analysis was performed to convert microvascular perfusion signals into two-dimensional spectrum and three-dimensional time-frequency scalogram.Changes of blood perfusion,velocity and blood cell concentration of kidney and pancreas were compared between SHRs and WKYs.Additionally,the differences of amplitudes of nitric oxide(NO)-dependent and NO-independent endothelial components were compared.Results:Compared with WKY group,SHR group exhibited decreased renal and pancreatic microvascular blood perfusion(P<0.05,P<0.01).Meanwhile,the bio-rhythmic of pancreatic microvascular vasomotion were disarranged in SHR group.The amplitude and frequency of microvascular vasomotion were both decreased in kidney and pancreas of SHR group(P<0.05 or P<0.01).The mean amplitudes of both NO-dependent and NO-independent endothelial components were significantly decreased in kidney and pancreas of SHR group(P<0.05 or P<0.01).Conclusion:Renal and pancreatic microcirculation are abnormal in SHRs,including decreased microcirculatory blood perfusion and impaired microvascular vasomotion.