Membrane stabilizing effect

Membrane stabilizing effects involve the inhibition or total abolishing of action potentials from being propagated across the membrane. This phenomenon is common in nerve tissues as they are the carrier of impulses from the periphery to the central nervous system. Membrane stabilization is the method through which local anesthetics work. They block the propagation of action potentials across the nerve cell thereby producing a nerve block.

Some beta-blockers also possess what is referred to as membrane stabilizing activity (MSA). This effect is similar to the membrane stabilizing activity of sodium channel blockers that represent Class I antiarrhythmics. MSA produced by beta-blockers reduces the rate of rise of the cardiac action potential and has other electrophysiological effects. However, MSA occurs only at very high concentrations and is not of clinical relevance, except after a large overdose

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