Sandbox WWC3: Difference between revisions

Sodium channels initiate action potentials in nerve and muscle cells. These electrical signals initiate the contraction of muscles and the release of neurotransmitters. The electrical signal is propagated when the sodium channel allows the influx of sodium ions. These positively charged ions depolarize the resting membrane potential of -70mV to +40mV, which creates the electrical signal that is sent along the length of the cell.The initial influx of sodium ions is often activated by the binding of a neurotransmitter to receptors on the post-synaptic membrane <ref>https://en.wikipedia.org/wiki/Neurotransmission</ref>. Then, as the sodium ions depolarize the membrane potential. more sodium channels open, and the action potential moves along the length of the muscle or nerve. The channels inactivate after 1-2ms <ref name = "physio">DOI: 10.1113/jphysiol.2011.224204</ref> and the depolarization is then reversed by the efflux of potassium ions out of potassium channel<ref name ="physio"/>. This information was first discovered by Hodgkin and Huxley in 1952<ref name ="physio"/>. For more information on the role of sodium channels in electrical signaling, click [https://en.wikipedia.org/wiki/Action_potential here].