The voltage dependence of ionic conductances such as those of sodium and potassium is the result of the voltage influence on the open and closed times of individual channels. This means that an understanding of the voltage dependence of the fraction of open channels will help to correlate the microscopic (single-channel) and macroscopic properties (total ionic current). The question arises as to how the channel goes from the open to the closed configuration and, in particular, how the voltage across the membrane regulates the state of the channel, a process known as voltage gating.
KeywordsSodium Channel Closed State Voltage Dependence Sodium Current Membrane Capacitance
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