Wolf G, Ziyadeh F N, Zahner G, Stahl R A
Department of Medicine, Division of Nephrology and Osteology, University of Hamburg, Germany.
Hypertension. 1996 Apr;27(4):897-905. doi: 10.1161/01.hyp.27.4.897.
Angiotensin II (Ang II) has growth-stimulatory properties on different renal cell types. However, possible growth effects of this vasoactive peptide on endothelial cells isolated from the glomerular microvasculature have not been formally investigated. Therefore, we isolated and characterized primary cultures of rat glomerular endothelial cells. We used a simple technique in which collagenase-treated glomeruli were sparsely plated in several 96-well culture plates and microscopically screened for cobblestone-like outgrowth. After two limiting dilutions, homogeneous cultures were obtained. Cells were characterized by positive staining for the endothelial markers factor VIII, CD 31, endothelial leukocyte adhesion molecule-1, and the lectin Bandeiraea simplificifolia. Ang II stimulated the synthesis and release of endothelin-1 in culture supernatants. Moreover, in contrast to syngeneic mesangial cells, glomerular endothelial cells expressed angiotensin-converting enzyme. Ang II stimulated a mild but significant proliferation of quiescent cells, as measured by [3H]thymidine incorporation and direct cell counting. This mitogenesis was transduced by losartan-blockade angiotensin type 1 receptors. Moreover, Ang II mediated phosphorylation of mitogen-activated protein kinase 2 and induction of transcripts for the immediate early gene Egr-1. Our results indicate that Ang II is a moderate mitogen for primary cultures of rat glomerular endothelial cells and activation of these metabolically active cells may play a role in the pathophysiology of several types of glomerulonephritis. Moreover, remodeling of glomerular endothelial cells by Ang II may be important in the progression of structural renal damage during the course of hypertensive injury.
血管紧张素 II（Ang II）对不同类型的肾细胞具有生长刺激特性。然而，这种血管活性肽对从肾小球微血管分离的内皮细胞可能产生的生长效应尚未得到正式研究。因此，我们分离并鉴定了大鼠肾小球内皮细胞的原代培养物。我们采用了一种简单的技术，即将经胶原酶处理的肾小球稀疏接种到多个 96 孔培养板中，并通过显微镜筛选鹅卵石样的细胞生长。经过两次有限稀释后，获得了均匀的培养物。通过对内皮标志物因子 VIII、CD 31、内皮白细胞黏附分子 -1 和凝集素单叶豆（Bandeiraea simplificifolia）进行阳性染色来鉴定细胞。Ang II 刺激培养上清液中内皮素 -1 的合成与释放。此外，与同基因系膜细胞不同，肾小球内皮细胞表达血管紧张素转换酶。通过 [³H]胸苷掺入和直接细胞计数测量，Ang II 刺激静止细胞发生轻度但显著的增殖。这种有丝分裂作用可被氯沙坦阻断血管紧张素 1 型受体所转导。此外，Ang II 介导丝裂原活化蛋白激酶 2 的磷酸化以及即刻早期基因 Egr -1 转录本的诱导。我们的结果表明，Ang II 是大鼠肾小球内皮细胞原代培养物的中度有丝分裂原，这些代谢活跃细胞的激活可能在几种类型的肾小球肾炎的病理生理学中起作用。此外，Ang II 对肾小球内皮细胞的重塑在高血压损伤过程中肾脏结构损伤的进展中可能很重要。
