SHEAR ACTIVATED CHANNELS IN CELL-ATTACHED PATCHES OF CULTURED BOVINE AORTIC ENDOTHELIAL-CELLS

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 str ess. The open state probability of IRK channels in cell-attached membr ane 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 induc es hyperpolarization and gating of single channel and whole cell IRK c urrents in BAECs.