Oxidant stress and endothelial membrane transport.
The endothelium modulates vascular tone, vasoreactivity, and permeability in response to agonist-stimulation. Much of the pathophysiology of oxidant-induced vascular injury can be attributed to endothelial cell dysfunction. In the past several years, the effects of oxidant stress on agonist-stimulated Ca(2+)-channels have been described. More recently, the effects of oxidant stress on several other endothelial membrane-transport systems have been elucidated. It now appears that inhibition of the agonist-stimulated Ca2+ channel is due at least in part to membrane depolarization via oxidant-activation of a Na(+)-permeable, nonselective cation channel. In this review, the effects of oxidant stress on ion transport through the agonist-stimulated Ca2+ influx channel, Na+ and K+ channels, Na+/K(+)-ATPase, Ca(2+)-ATPase, and the Na+/K+/2Cl- cotransporter are discussed. The interrelated effects of oxidant stress on these endothelial membrane transport pathways are considered, and the net effect on Ca2+ signaling is described.
Elliott
S J
SJ
Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA.
Koliwad
S K
SK
D000818:Animals; D017920:Antiporters / Q000378:metabolism; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000502:physiology; D002462:Cell Membrane / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000502:physiology*; D006801:Humans; D008954:Models, Biological; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress; D011188:Potassium / Q000378:metabolism; D015221:Potassium Channels / Q000502:physiology; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism
D017920:Antiporters; D015220:Calcium Channels; D016877:Oxidants; D015221:Potassium Channels; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium; D002118:Calcium