激光多普勒流量计观察单侧输尿管梗阻大鼠双侧肾皮质微循环血流变化

目的:用激光多普勒流量计观察单侧输尿管梗阻大鼠双侧肾皮质微循环血流的变化,探讨梗阻侧肾间质纤维化的发病机制及健侧肾的代偿机制。方法:成年雌性SD大鼠,随机分为假手术组和模型组。假手术组仅将输尿管游离但不结扎离断,模型组行单侧输尿管结扎术。术后第7、14和21天随机选取并处死各组中的6只大鼠,观察双肾病理学改变,并检测双侧肾皮质微循环血流。结果:H-E染色显示假手术组双侧肾各时间点肾单位结构正常,间质无增宽;模型组大鼠梗阻侧肾术后7 d出现早期间质纤维化的病理改变,并随梗阻时间延长逐渐加重;健侧肾小球系膜细胞增生并随代偿时间延长逐渐增多。肾皮质微循环血流,与假手术组比较,模型组大鼠健侧肾皮质微循环血流显著增加,梗阻侧肾皮质微循环灌注量先增加后进行性降低。结论:血液流变学改变、梗阻侧肾皮质微循环血流灌注量进行性减少是肾间质纤维化的发病机制之一;而健侧肾皮质微循环血流灌注量增高,在一定程度上有利于健侧肾的功能代偿。

Changes of microcirculation blood flow in the bilateral renal cortex of rats with unilateral ureteral obstruction by laser doppler flowmetry

Objective:To observe the microcirculation blood flow in the bilateral renal cortex of rats with unilateral ureteral obstruction by laser doppler flowmetry and to explore the compensatory mechanism of the kidney of the healthy side.Methods:Totally 36 adult female SD rats were randomly divided into sham operation group and model group.The ureters of rats in the sham group were manipulated but not ligated.Whereas,the left unilateral ureter of rats in the model group was ligated.A total of 6 rats from each group were randomly selected and killed on day 7,14 and 21 after unilateral ureteral obstruction.During the process,the pathological changes and the renal cortex microcirculation blood flow of each kidney were detected.Results:In the sham operation group,the structure of renal unit of bilateral kidneys was normal at each time point with no increase of stroma.In the model group,pathological changes of early interstitial fibrosis appeared at day 7 after the operation of the side of the obstructed kidney,and gradually increased with the time of obstruction.The glomerular mesangial cells of contralateral kidney proliferated and gradually increased with the obstruction time.Compared with the sham operation group,microcirculation blood flow of the contralateral renal cortex increased significantly in the model group,and the microcirculation perfusion of the obstructed kidney increased first and then decreased.Conclusion:The change of blood rheology and the decrease of the renal microcirculation perfusion in the side of the obstruction is one of the pathological reasons for the renal interstitial fibrosis.The increase of microcirculation perfusion of the kidney of the healthy side is beneficial to the compensatory mechanism of the kidney of the healthy side.