Abstract
Outward currents in isolated, internally-perfused snail neurons were slowed and reduced in amplitude by replacement of external K with Na, Cs, or tris. This behavior is not predicted by electrodiffusion theory, but can be described by a second-order kinetic model. The effect of potassium replacement is to reduce the rate constant for channel opening by aout 25% without affecting the rate constant for channel closing. The open channels may be stabilized by external potassium ions, thus increasing the mean channel open time.
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Junge, D. External K+ ions increase rate of opening of outward current channels in snail neurons. Pflugers Arch. 394, 94–96 (1982). https://doi.org/10.1007/BF01108314
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DOI: https://doi.org/10.1007/BF01108314