In vivo vizualization of glomerular microcirculation microcirculation in AT1 a knock-out mice. -Role of anigiotensinII-

我们最近开发了一种划时代的技术，可以用活着的针型透镜探头视频显微镜直接显示大型动物(犬和人)的肾小球微循环。为了直观地显示小动物如大鼠和小鼠的肾小球微循环，我们将该系统的探头从针状透镜探头改进为笔状探头。首先，我们成功地在静脉注射血管紧张素II(AT1)拮抗剂(Losartan)前后对正常Wistar大鼠和链脲佐菌素诱导的糖尿病大鼠进行了活体直接可视化肾小球微循环的初步实验。在正常大鼠，给予氯沙坦(1、3和10 mg/kg)后，传入和传出小动脉直径均延长，并呈剂量依赖关系。在糖尿病大鼠，给予氯沙坦后，传入小动脉的直径没有改变，但传出小动脉的直径与正常大鼠相同。第二，我们最近成功地进行了小鼠肾小球微循环的活体可视化和血管紧张素II影响下的肾小球传出小动脉梗塞的矢量图像处理。

We have recently developed an epoch-making technique to directly visualize a glomerular microcirculation of the kidney with an intravital needle type lens-probe videomicroscopy for a large animal (canine and human). In order to directly visualize a glomerular microcirculation for smaller animals such as rat and mouse, we improved the tip of probe of this system from a needle type lens-probe to a pencil type one.First, we succeeded as preliminary experiments in intravital direct vizualization of glomerular microcirculation in normal Wistar rats and streptorozocine induced diabetic rats under pre- and post intravenous administration of angiotensin II (AT1) antagonist (Losartan). In normal rats, the diameters of afferent and efferent arterioles were extended after administrating Losartan (1, 3 and 10 mg/kg) relating with dose dependency. In the diabetic rats, the diameters of afferent arterioles were not changed but those of efferent arterioles were extended as same as the normal rats after the administration of Losartan.Second, we could recently succeed in in vivo vizualization of glomerular microcirculation of mice and vector image processing of contarction of efferent arterioles of the glomeruli under the influence of angiotensin II administration.