Potassium channels and membrane potential in the modulation of intracellular calcium in vascular endothelial cells.
The endothelium plays a vital role in the control of vascular functions, including modulation of tone; permeability and barrier properties; platelet adhesion and aggregation; and secretion of paracrine factors. Critical signaling events in many of these functions involve an increase in intracellular free Ca(2+) concentration ([Ca(2+)](i)). This rise in [Ca(2+)](i) occurs via an interplay between several mechanisms, including release from intracellular stores, entry from the extracellular space through store depletion and second messenger-mediated processes, and the establishment of a favorable electrochemical gradient. The focus of this review centers on the role of potassium channels and membrane potential in the creation of a favorable electrochemical gradient for Ca(2+) entry. In addition, evidence is examined for the existence of various classes of potassium channels and the possible influence of regional variation in expression and experimental conditions.
Adams
David J
DJ
School of Biomedical Sciences, University of Queensland, Brisbane, Queensland, Australia. dadams@uq.edu.au
Hill
Michael A
MA
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000502:physiology*; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D042541:Intracellular Space / Q000502:physiology; D015640:Ion Channel Gating / Q000502:physiology; D008564:Membrane Potentials / Q000502:physiology*; D015221:Potassium Channels / Q000145:classification* / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*
D015221:Potassium Channels; D002118:Calcium