Hypoxic induction of adrenomedullin in cultured human umbilical vein endothelial cells
Hypoxic induction of adrenomedullin in cultured human umbilical vein endothelial cells
复制标题
DOI：
10.1097/00004872-200103001-00013
复制
发表时间：
2001-03-01
影响因子：
4.9
通讯作者：
Fujita, T
中科院分区：
文献类型：
--
作者：
Ogita, T;Hashimoto, E;Fujita, T
目的探讨缺氧对人脐静脉内皮细胞（HUVEC）肾上腺髓质素（adrenomedullin，ADM）基因表达和分泌的影响及其机制。方法以HUVEC为实验对象，分别在缺氧或常氧条件下培养1 ~ 24 h，采用北方印迹法和放射免疫法检测HUVEC中ADM的表达，肾上腺髓质素基因调控的转录成分通过核流出实验进行评估，用放线菌素D实验测定肾上腺髓质素mRNA的半衰期（1-3%氧）可使HUVEC肾上腺髓质素mRNA和蛋白表达显著增加，这种增加与氧张力成反比，且在21%氧环境中可逆转。核溢流实验表明肾上腺髓质素基因转录速率增加。结论低氧通过转录和转录后机制促进HUVEC肾上腺髓质素基因的表达和分泌。肾上腺髓质素的低血压诱导可能在血管系统中发挥病理生理作用。
Objectives The current study evaluated the hypoxic induction of adrenomedullin gene expression and secretion, and its mechanism in cultured human umbilical vein endothelial cells (HUVEC),Methods HUVEC were exposed to hypoxia or normoxia as controls for 1 to 24 h, Using Northern blot analysis and a radioimmunoassay, we evaluated adrenomedullin expression in HUVEC, The transcriptional component of adrenomedullin gene regulation was assessed by nuclear run-off experiments, and adrenomedullin mRNA half-life was measured by actinomycin D experiments.Results We found that hypoxic conditions (1-3% oxygen) significantly increased adrenomedullin mRNA and protein in HUVEC, This increase was inversely proportional to oxygen tension and was reversible upon re-exposure to a 21% oxygen environment Nuclear run-off experiments revealed the enhanced transcriptional rate of adrenomedullin gene. Next, actinomycin D experiments revealed the enhanced adrenomedullin mRNA stability,Conclusions These results indicate that hypoxia increases adrenomedullin gene expression and secretion in HUVEC by transcriptional and post-transcriptional mechanisms. Hypoxic induction of adrenomedullin may play a pathophysiological role in the vascular systems.