Saito M, Homma S, Yamatsu I, Sato M, Ohshima N
Tsukuba Research Laboratories, Eisai Co., Ltd., Ibaraki, Japan.
Jpn J Pharmacol. 1994 Oct;66(2):221-9. doi: 10.1254/jjp.66.221.
The aim of the present study was to visualize the superficial glomeruli of the Munich-Wistar (MW) rat and to characterize the responses of the renal microvasculature to endothelin-1 (ET-1). We first examined the distribution of superficial glomeruli of the MW rat compared to that in a control strain (Wistar rat). Secondly, we examined the effects of ET-1 on the renal microcirculation of the MW rat. The right kidney was perfused with a Krebs-Ringer solution containing fluorescein isothiocyanate dextran (FITC-dextran) and was visualized under an epi-illuminated fluorescence microscope system. Changes in perfusion pressure and diameter of the microvessels accompanying the administration of ET-1 (10 fmole-300 pmole) were measured. The number of superficial glomeruli was greater in the MW rat than in the Wistar rat. ET-1 had long-lasting and dose-dependent pressor effects. Perfusion pressure showed a 3.5-fold increase compared with the control, and the afferent arterioles showed greater dose-dependent vasoconstriction than the efferent arterioles. These findings suggest that the MW rat is a useful animal model for the study of renal microcirculation and that the renal microcirculation is extremely sensitive to ET-1.
本研究的目的是观察慕尼黑-威斯塔（MW）大鼠的浅表肾小球，并描述肾微血管对内皮素-1（ET-1）的反应。我们首先比较了MW大鼠与对照品系（威斯塔大鼠）浅表肾小球的分布情况。其次，我们研究了ET-1对MW大鼠肾微循环的影响。用含有异硫氰酸荧光素葡聚糖（FITC-葡聚糖）的 Krebs-Ringer 溶液灌注右肾，并在落射荧光显微镜系统下进行观察。测量给予ET-1（10飞摩尔 - 300皮摩尔）时伴随的灌注压力和微血管直径的变化。MW大鼠的浅表肾小球数量比威斯塔大鼠多。ET-1具有持久的剂量依赖性升压作用。与对照组相比，灌注压力增加了3.5倍，且入球小动脉比出球小动脉表现出更大的剂量依赖性血管收缩。这些发现表明，MW大鼠是研究肾微循环的有用动物模型，并且肾微循环对ET-1极其敏感。
