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of sodium ions is intimately related to the electrical potential across a membrane. Depolarization often occurs via the influx of sodium ions to the intracellular region. Given that sodium ions have a positive charge, the intracellular region becomes less negatively charged relative to the
84:. The opening of Na channels allows Na inflow, which, in turn, further depolarizes the membrane. Additional depolarization activates additional Na channels. This cycle leads to a very rapid rise in Na conductance (g
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open to re-polarize the membrane potential. This positive feedback loop means that the closer these voltage-gated Na channels are to each other, the lower the threshold of
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for example, revolves around changes in the electrical potentials across their membranes. In a healthy cell at rest, the
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is a key component of membrane physiology that describes bioelectrical impulses, especially prevalent in
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region. Depolarization refers to when the intracellular region is neutralized to be at the same
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An understanding of membrane physiology is needed in order to understand how
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Finger, Stanley; Piccolino, Marco (8 September 2011).
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Representation of biological membrane depolarization
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128:relative to the extracellular region. The
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42:tissues. It was identified by British
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112:. Signalling between cells, such as
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57:The Hodgkin cycle represents a
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104:Importance in cell physiology
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77:in order to activate
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94:potassium channels
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59:positive feedback
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