The gating currents of sodium channels: pore-population-size effects.
Sodium-channel behavior has been modeled in order to determine the answer to the following question: How large must a population of "on-off" sodium pores be before the inherently random behavior of the individual channels becomes smoothed to yield the expected gating current-conductance relationships which would be predicted from an infinite pore array? Results of this analysis show that for the "opening" situation, an excellent fit was obtained whenever more than about 10 pores were considered. Significant discrepancies were observed in the "closing" situation, however, for pore arrays of 50 or less. Marked hysteresis is apparent in the behavior of small port populations.
D008566:Membranes; D008954:Models, Biological; D010539:Permeability; D012964:Sodium / Q000378:metabolism*
D012964:Sodium