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Updated: Jul 29, 2026

Use of Label-free Optical Biosensors to Detect Modulation of Potassium Channels by G-protein Coupled Receptors
Published on: February 10, 2014
Channel-like function of the Na,K pump probed at microsecond resolution in giant membrane patches
1Department of Physiology, University of Texas Southwestern Medical Center, Dallas 75235.
Abstract:
Ion transporters can be thought of as ion channels that open and close only at one end at a time. As in real channels, ions may cross through an electrical field as they diffuse into and bind within the transporter pore, thereby generating electrical current. Extracellular sodium binding by the sodium potassium (Na,K) pump is associated with ultrafast charge movements in giant cardiac membrane patches. The charge movements are complete within 4 microseconds. They occur only when binding sites are open to the extracellular side, and they are abolished by ouabain and by the removal of extracellular sodium. Fast extracellular ion binding may be the exclusive source of Na,K pump electrogenicity.
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