Nav1.4

Nav1.4 is a voltage-gated sodium channel that is primarily expressed in skeletal muscle tissue. It is encoded by the SCN4A gene in humans. This channel plays a crucial role in the generation and propagation of action potentials in muscle cells, which are essential for muscle contraction.

Function

Nav1.4 channels are responsible for the rapid influx of sodium ions (Na⁺) into muscle cells, which depolarizes the cell membrane and initiates an action potential. This process is vital for the proper functioning of skeletal muscles, allowing for voluntary movement and reflexes.

Clinical Significance

Mutations in the SCN4A gene can lead to a variety of neuromuscular disorders. Some of these include:

• Hyperkalemic periodic paralysis
• Paramyotonia congenita
• Potassium-aggravated myotonia
• Congenital myasthenic syndrome

These conditions are characterized by episodes of muscle weakness or stiffness, which can be triggered by factors such as exercise, temperature changes, or potassium levels.

Research and Therapeutic Implications

Understanding the function and regulation of Nav1.4 channels is important for developing treatments for the associated neuromuscular disorders. Research is ongoing to find pharmacological agents that can modulate the activity of these channels to alleviate symptoms in affected individuals.

See Also

• Voltage-gated sodium channel
• Skeletal muscle
• Action potential

External Links

• [Nav1.4 at IUPHAR/BPS Guide to PHARMACOLOGY](https://www.guidetopharmacology.org/GRAC/ObjectDisplayForward?objectId=528)
• [SCN4A gene information at NCBI](https://www.ncbi.nlm.nih.gov/gene/6329)