Publications by authors named "Johannes Wiecha"

The proliferation of endothelial cells plays a crucial role in the development of intraplaque angiogenesis (IPA). IPA is a major source of intraplaque hemorrhage and therefore contributes to the destabilization of atherosclerotic plaques. Therefore, the aim of the present study was to examine, whether sildenafil inhibits endothelial cell growth.

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Intracellular cGMP is an important second messenger in endothelial cells. Because Ca(2+)-activated K(+) channels with large conductance (BK(Ca)) have been shown to regulate endothelial cell functions, the aim of the present study was to examine whether sildenafil modulates BK(Ca) activity in cultured human endothelial cells. Changes of the endothelial cell membrane potential were analyzed using the fluorescence dye DiBAC.

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The inward rectifier K+ current (K(ir)) determines the resting membrane potential of endothelial cells. Basic fibroblast growth factor (bFGF) has been shown to activate K(ir) and acts as angiogenic factor and vasodilator. In contrast, nicotine has been demonstrated to reduce endothelium-dependent vasorelaxation by increasing radical formation.

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Activation of Ca2+-activated K+ channels (BK(Ca)) has been shown to be an important step in the basic fibroblast growth factor (bFGF)-induced proliferation of endothelial cells. In this study, we investigate the signaling cascades of BK(Ca) modulation by bFGF. Using the patch-clamp technique, bFGF (50 ng/ml) significantly increased the BK(Ca) open-state probability in cultured endothelial cells derived from human coronary arteries after 6 min (n=26, p<0.

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Background: Regular moderate alcohol (EtOH) intake seems to protect against both coronary artery disease and ischemic stroke, whereas the risk increases with heavy EtOH consumption. Effects of EtOH on endothelial cell function may be relevant to these disparate effects. Potassium channels play an important role in the regulation of endothelial cell functions.

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The proliferation of endothelial cells is induced by oxidized low-density lipoprotein (oxLDL) and its major component, lysophosphatidylcholine (LPC). The aim of this study was to investigate the effect of statins on the proliferation of endothelial cells derived from human umbilical cord veins (HUVEC). Cerivastatin, simvastatin and fluvastatin caused a dose-dependent inhibition of endothelial cell growth (n=12; P<.

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Objective: Inward rectifier K+ currents (K(ir)) determine the resting membrane potential and thereby modulate essential Ca2+-dependent pathways, like cell growth and synthesis of vasoactive agents in endothelial cells. Basic fibroblast growth factor (bFGF) acts as a vasodilatator and angiogenic factor. Therefore, we investigated the effect of bFGF on K(ir) and assessed the role in proliferation and nitric oxide (NO) formation of endothelial cells.

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Statins are known to counteract the process of arteriosclerosis by exerting direct pleiotropic effects on vascular endothelium. The aim of this study was to investigate a possible effect of cerivastatin on endothelial Ca(2+)-activated K+ channels (BK(Ca)) and to assess their contribution to cerivastatin-mediated changes of endothelial nitric oxide (NO) production and proliferation. Membrane potential was measured using bis-1,3-dibutylbarbituric acid-trimethine oxonol-fluorescence imaging.

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Objective: Oxidized low-density lipoprotein (oxLDL) plays an important role in causing endothelial dysfunction and initiating atherosclerosis. Some of the endothelial functions have been shown to be modulated by changes in cellular electrophysiological properties. Therefore, we analysed the effect of oxLDL on endothelial Ca(2+)-activated K(+) channels (BK(Ca)) and its contribution to oxLDL-mediated changes of proliferation and syntheses of nitric oxide (NO).

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