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Neuronal Signaling. A Simple Thermodynamic Process Involving Complex Membrane Proteins

  • Franco Conti

Abstract

Since the classical work of Hodgkin and Huxley1 the complex phenomenology of the transmission of electrical signals along nerve fibers is fully understood in terms of voltage and time dependence of the nerve membrane conductance. Also included in the Hodgkin-Huxley description of nerve excitation was the notion that the time delays characterizing the changes in membrane permeability must arise from simple voltage-dependent reactions involving specific molecular structures within the membrane itself. What could not be foreseen in 1952 was the fact that these structures, nowadays named ion channels, were bound to become one of the most important unifying concepts of membrane biophysics. It is now known that most functions of biological membranes are based on the performance of such specialized proteins, embedded in a common lipid bilayer matrix and characterized by their capability of assuming different conformations with probabilities which are determined, and thereby modulated, by the chemical and physical properties of their environment. Thus, both propagating action potentials (purely electrically driven) and synaptic signals (mediated by chemical agonists) are based on the same type of molecular event involving the opening of an aqueous pore within a membrane-spanning protein. With the advent of the patch-clamp technique pioneered by Neher and Sakmann2 the unitary electrical events produced by several kinds of ionic channels can be directly observed on the screen of an oscilloscope.3

Keywords

Sodium Channel Channel Protein Sodium Current Neuronal Signaling Charge Redistribution 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1986

Authors and Affiliations

  • Franco Conti
    • 1
  1. 1.Istituto di Cibernetica e BiofisicaCNRGenovaItaly

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