Hydrogen peroxide induces intracellular calcium oscillations in human aortic endothelial cells
Hydrogen peroxide induces intracellular calcium oscillations in human aortic endothelial cells
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DOI：
10.1161/01.cir.97.3.268
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发表时间：
1998-01-27
期刊：
影响因子：
37.8
通讯作者：
Ziegelstein, RC
中科院分区：
文献类型：
--
作者：
Hu, QH;Corda, S;Ziegelstein, RC
背景-由于血管内皮细胞暴露于缺血/再灌注和多形核白细胞或单核细胞产物引起的氧化应激，因此进行了研究以检查过氧化氢的作用（1 μ mol/L至10 mmol/L）对内皮细胞Ca 2+信号传导的影响，方法和结果-低浓度（1 - 10 μ mol/L），过氧化氢不影响亚融合的、负载吲哚1的人主动脉内皮单层细胞内Ca 2+浓度，在100 μ mol/L过氧化氢浓度下，细胞内游离Ca 2+在4.2 +/- 0.9分钟内从125.3 +/- 6.8逐渐增加到286.3 +/- 19.9 nmol/L，在12.0 +/- 1.1分钟内，以0.7 +/- 0.1 min（-1）的频率出现约1 μ mol/L的瞬时峰电位，随后出现几个幅度降低的峰电位，在这些振荡后，细胞内Ca 2+达到543.4 +/- 64.0 nmol/L的平台，其维持在基线水平以上> 5分钟，然后在大多数单层中在过氧化氢洗脱时部分可逆，细胞内Ca ~（2+）振荡通常观察到当单层细胞暴露于100至500 μ mol/L的过氧化氢。较高浓度的过氧化氢（1和10 mmol/L）增加细胞内Ca 2+，但很少（2/6的单层在1 mmol/L）或从来没有（在10 mmol/L）刺激细胞内Ca 2+振荡。在过氧化氢刺激之前或在建立的反应过程中从缓冲液中除去Ca 2+并不能阻断细胞内Ca 2+对100 μ mol/L过氧化氢的反应，但在用咖啡因、组胺、或毒胡萝卜素消除Ca 2+振荡。结论-过氧化氢诱导浓度依赖性细胞内Ca 2 +振荡在人类内皮细胞，这是由于释放内质网Ca 2+存储。由于氧化剂的产生似乎发生在微摩尔范围内的postisemic/缺氧内皮细胞，并与受损的内皮依赖性舒张，微摩尔浓度的过氧化氢对内皮细胞Ca 2+信号转导的影响在本研究中描述的postisemic内皮功能障碍的发病机制可能是重要的。
Background-Because the vascular endothelium is exposed to oxidant stress resulting from ischemia/reperfusion and from the products of polymorphonuclear leukocytes or monocytes, studies were performed to examine the effect of hydrogen peroxide (1 mu mol/L to 10 mmol/L) on endothelial Ca2+ signaling,Methods and Results-At low concentrations (1 to 10 mu mol/L), hydrogen peroxide did not affect intracellular Ca2+ concentration in subconfluent, indo 1-loaded human aortic endothelial monolayers, At a concentration of 100 mu mol/L hydrogen peroxide, intracellular free Ca2+ gradually increased from 125.3 +/- 6.8 to 286.3 +/- 19.9 nmol/L over 4.2 +/- 0.9 minutes before repetitive Ca2+ oscillations were observed, consisting of an initial large, transient spike of approximate to 1 mu mol/L followed by several spikes of decreasing amplitudes at a frequency of 0.7 +/- 0.1 min(-1) over 12.0 +/- 1.1 minutes, After these oscillations, intracellular Ca2+ reached a plateau of 543.4 +/- 64.0 nmol/L, which was maintained above baseline levels for > 5 minutes and then partially reversible on washout of hydrogen peroxide in most monolayers, Intracellular Ca2+ oscillations were typically observed when monolayers were exposed to 100 to 500 mu mol/L hydrogen peroxide. Higher concentrations of hydrogen peroxide (1 and 10 mmol/L) increased intracellular Ca2+ but only rarely (2 of 6 monolayers at 1 mmol/L) or never (at 10 mmol/L) stimulated intracellular Ca2+ oscillations. Removal of Ca2+ from the buffer either before hydrogen peroxide stimulation or during an established response did not block intracellular Ca2+ oscillations in response to 100 mu mol/L hydrogen peroxide, but prior depletion of an intracellular Ca2+ store with either caffeine, histamine, or thapsigargin abolished Ca2+ oscillations.Conclusions-Hydrogen peroxide induces concentration-dependent intracellular Ca2+ oscillations in human endothelial cells, which results from release of an endoplasmic reticulum Ca2+ store. Because oxidant production appears to occur In the micromolar range in the postischemic/anoxic endothelium and is associated with impaired endothelium-dependent relaxation, the effects of micromolar concentrations of hydrogen peroxide on endothelial Ca2+ signaling described in the present study maybe important in the pathogenesis of postischemic endothelial dysfunction.