From Brain to Bilayer
Contemporary studies on the molecular basis of membrane excitability spring from the pivotal conclusion reached by Hodgkin and Huxley (1952b) that the currents that generate an action potential must flow through a sparse array of voltage-sensitive conducting sites in the plasmalemma. They further showed that the squid axon membrane possessed two functionally distinct transmembrane pathways, which were selective for sodium and potassium ions, respectively (Hodgkin and Huxley, 1952a). These are the voltage-gated sodium and potassium “channels,” and they are, indeed, discrete macromolecules that form hydrophilic pores through the membrane (Hille, 1984).
KeywordsSodium Channel Planar Lipid Bilayer Apparent Dissociation Constant Sparse Array Planar Bilayer
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