Glomerular actions of endothelin in vivo.
Glomerular actions of endothelin in vivo.
复制标题
内皮素在体内的肾小球作用。
DOI：
10.1172/jci114079
复制
发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Ichikawa,I
中科院分区：
文献类型：
--
作者：
Kon,V;Yoshioka,T;Fogo,A;Ichikawa,I
在Munich-Wistar大鼠中，将微量移液器插入左主肾动脉的一级分支，并连续输注人/猪内皮素（0.4 ng/min）。微穿刺测量显示同一左肾皮质微循环内的实质性差异：与未灌注内皮素的肾小球相比，暴露于内皮素的肾小球的SNGFR低约35%（P <0.005）。同样，内皮素暴露的肾小球血浆流速降低约38%（P <0.001）。内皮素暴露肾小球的低灌注和低滤过反映了传入和传出小动脉阻力的增加。两组肾小球毛细血管超滤系数无差异。我们还研究了在研究前48小时进行25分钟肾动脉夹闭的肾脏。将抗内皮素抗体注入主肾动脉的一个分支改善了缺血后肾单位的血管收缩特征：在皮质微循环中，暴露于抗内皮素抗体的肾小球的SNGFR为27.0 +/- 3.1 nl/min，而未灌注抗体的肾小球的SNGFR为17.4 +/- 1.7（P <0.001）。同样地，暴露于抗内皮素抗体的肾小球的肾小球血浆流速更高（128.7 +/- 14.4 nl/min vs. 66.6 +/- 5.6，P <0.005）。抗体暴露的肾小球中传入和传出小动脉的阻力显著降低。因此，这表明内皮素可能从受损的内皮细胞中释放出来，在缺血后肾脏的低灌注和低滤过中起着重要的中介作用。图像
In Munich-Wistar rats, a micropipette was inserted into a first-order branch of the left main renal artery and continuously infused with human/porcine endothelin (0.4 ng/min). Micropuncture measurements revealed substantial differences within the cortical microcirculation of the same left kidney: SNGFR was some 35% lower in glomeruli exposed to endothelin compared with non-endothelin-perfused glomeruli (P less than 0.005). Similarly, glomerular plasma flow rate was some 38% lower in the endothelin-exposed glomeruli (P less than 0.001). The hypoperfusion and hypofiltration in the endothelin-exposed glomeruli reflected an increase in resistances in the afferent and efferent arterioles. There was no difference in the value of the glomerular capillary ultrafiltration coefficient between the two populations of glomeruli. We also studied kidneys that underwent 25 min of renal artery clamping 48 h before study. Antiendothelin antibody infused into one of the branches of the main renal artery ameliorated the vasoconstriction characteristic of postischemic nephrons: within the cortical microcirculation, the SNGFR in glomeruli exposed to antiendothelin antibody was 27.0 +/- 3.1 nl/min as compared with 17.4 +/- 1.7 measured in glomeruli not perfused with the antibody (P less than 0.001). Similarly, glomerular plasma flow rate was higher in the glomeruli exposed to antiendothelin antibody (128.7 +/- 14.4 nl/min vs. 66.6 +/- 5.6, P less than 0.005). Resistances in both the afferent and efferent arterioles were substantially lower in the antibody-exposed glomeruli. It is, therefore, suggested that endothelin, presumably released from damaged endothelium, may play an important intermediary role in the hypoperfusion and hypofiltration observed in postischemic kidneys.Images