Shear activated channels in cell-attached patches of cultured bovine aortic endothelial cells
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We investigated the response of inward rectifier K+ (IRK) currents in bovine aortic endothelial cells (BAECs) to shear stress. Shear evoked reversible hyperpolarization in current clamped BAECs. Voltage clamped BAECs exhibited large inward and small outward whole cell K+ currents blocked by cesium and increased in amplitude by exposure to shear stress. The open state probability of IRK channels in cell-attached membrane patches was increased within minutes of exposure to shear stress. IRK channels in inside-out patches were activated by increases in [Ca2+]i from 10−7 to 10−6 mM. We demonstrate that shear stress induces hyperpolarization and gating of single channel and whole cell IRK currents in BAECs.
Key wordsPotassium channels membrane potential hyperpolarization endothelial cells shear stress inward rectifier ion channels calcium sensitivity
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