The resting membrane potential of minus seventy volts is maintained by a sodium/potassium transporter that transports sodium ions out of the cell and potassium ions in. Voltage gated sodium and potassium channels are closed. In response to a nerve impulse, some sodium channels open, allowing sodium ions to enter the cell. The membrane starts to depolarize; in other words, the charge across the membrane lessens. If the membrane potential increases to the threshold of excitation, all the…

This diagram shows how sodium and potassium ions are pumped through protein channels. The sodium ions are pumped out of the cell, while potassium is pumped into the cell. The movement of these ions creates resting potential and action potential.

Sodium-Channel Blockers (Class I Antiarrhythmics): Ventricular action potential with Class IA, IB and IC antiarrhythmic drugs

Sodium-Channel Blockers (Class I Antiarrhythmics): Ventricular action potential with Class IA, IB and IC antiarrhythmic drugs

The molecular genetics of Marfan syndrome and related microfibrillopathies -- Robinson and Godfrey 37 (1): 9 -- Journal of Medical Genetics

The diagnosis of Liddle syndrome by identification of a mutation in the beta subunit of the epithelial sodium channel. -- Jackson et al. 35 510 -- Journal of Medical Genetics

Nerve Impulse Transmission within a Neuron: Action Potential

Learn more about nerve impulse transmission within a neuron: action potential in the Boundless open textbook. Signals are transmitted from neuron to neuron via an action potential, when the axon membrane rapidly depolarizes and repolarizes.

Now where was I.   If you remember we have been examining how nerves fire. It is important because all of the problems of MS are caused by the nerves not functioning well enough or because they are over excited and firing too much. I got a bit side tracked by the B cell story. So to recap When a nerve impulse is transmitted it moves because of the action of sodium channels. The outside of the cell is normally more electrically positive than the inside of the cell.  So when the stimulus comes…

Now where was I. If you remember we have been examining how nerves fire. It is important because all of the problems of MS are caused by the nerves not functioning well enough or because they are over excited and firing too much. I got a bit side tracked by the B cell story. So to recap When a nerve impulse is transmitted it moves because of the action of sodium channels. The outside of the cell is normally more electrically positive than the inside of the cell. So when the stimulus comes…

De novo mutations of voltage-gated sodium channel alphaII gene SCN2A in intractable epilepsies.  - PubMed - NCBI

De novo mutations of voltage-gated sodium channel alphaII gene SCN2A in intractable epilepsies. - PubMed - NCBI

Procainamide (Pronestyl, Procan, Procanbid) is an antiarrhythmic used for cardiac arrhythmias, classified as class Ia. It is a sodium channel blocker which blocks open sodium channels and prolongs the cardiac action potential (outward potassium (K+) currents may be blocked). This results in slowed conduction, and ultimately the decreased rate of rise of the action potential, which may result in widening of QRS on electrocardiogram. It is a hapten. It is metabolized by N-acetyltransferase.

Procainamide (Pronestyl, Procan, Procanbid) is an antiarrhythmic used for cardiac arrhythmias, classified as class Ia. It is a sodium channel blocker which blocks open sodium channels and prolongs the cardiac action potential (outward potassium (K+) currents may be blocked). This results in slowed conduction, and ultimately the decreased rate of rise of the action potential, which may result in widening of QRS on electrocardiogram. It is a hapten. It is metabolized by N-acetyltransferase.

A de novo Mutation in the SCN4A Gene Causing Sodium Channel Myotonia - Europe PMC Article - Europe PMC

A de novo Mutation in the SCN4A Gene Causing Sodium Channel Myotonia - Europe PMC Article - Europe PMC

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