Open AccessOuabain at pathological concentrations might induce damage vascular endothelial cells
Author(s) -
REN Yanping,
HUANG Ruowen,
LÜ Zhuoren
Publication year - 2006
Publication title -
acta pharmacologica sinica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.514
H-Index - 90
eISSN - 1745-7254
pISSN - 1671-4083
DOI - 10.1111/j.1745-7254.2006.00244.x
Subject(s) - ouabain , endothelium , endothelial stem cell , downregulation and upregulation , umbilical vein , microbiology and biotechnology , biology , cell growth , endocrinology , medicine , chemistry , in vitro , biochemistry , sodium , gene , organic chemistry
Aim: To examine the time‐ and dose‐dependent effects of ouabain on human umbilical vein endothelial cells (HUVEC) in vivo , and the changes in aortic endothelium and the different expression levels of Kv4.2 in vitro. Methods: The proliferation of HUVEC and cell death were determined by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2 H ‐tetrazolium bromide (MTT) assay, the incorporation of [ 3 H]TdR, trypan blue staining, and lactate dehydrogenase (LDH) release. The response of endothelial cells to ouabain was explored with a complementary DNA microarray and a candidate gene was found. “Ouabain‐sensitive” hypertensive rats were established by chronic administration of ouabain. Changes in the aortic endothelium were observed by electron microscopy, and the expression level of Kv4.2 in different animals was studied by using real‐time quantitative reverse transcription‐ polymerase chain reaction (RT‐PCR). Results: Ouabain stimulated the proliferation of HUVEC at physiological concentrations (0.3–0.9 nmol/L). Ouabain at pathological concentrations (0.9–1.8 nmol/L) inhibited proliferation and induced cell death. mRNA profile analysis indicated that 340 genes were differentially expressed after ouabain treatment: 145 were upregulated, of which 6 were upregulated significantly, including KCND2 (encoding the potassium voltagegated channel shal‐related subfamily member 2). The upregulated genes were mainly related to cell metabolism and transcription. In ouabain‐sensitive hypertensive rats, the aortic endothelium was damaged and Kv4.2 (coded by KCND2 ) was over‐expressed. Conclusion: The physiological role of ouabain in HUVEC might involve the control of growth and metabolism. Ouabain at pathological concentrations might affect the structure and function of the vascular endothelium by modification of expression of the KCND2 gene, and participate vascular remodeling in hypertension.