Mutations in Nav1.4 and Nav1.5 α-subunits have been associated with muscular and cardiac channelopathies, respectively. Despite intense research on the structure and function of these channels, a lot of information is still missing to delineate the various physiological and pathophysiological processes underlying their activity at the molecular level. Nav1.4 and Nav1.5 sequences are similar, su...

The nondystrophic myotonias and primary periodic paralyses are an important group of genetic muscle diseases characterized by dysfunction of ion channels that regulate membrane excitability. Clinical manifestations vary and include myotonia, hyperkalemic and hypokalemic periodic paralysis, progressive myopathy, and cardiac arrhythmias. The severity of myotonia ranges from severe neonatal presen...

Hypokalemic Periodic Paralysis (HypoPP) is a condition that causes episodes of extreme muscle weakness typically beginning in childhood or adolescence. The disorder three to four times more commonly clinically expressed men. Mutations the CACNA1S (calcium voltage-gated channel subunit alpha 1 S) SCN4A (sodium 4) gene can cause Paralysis. primary form genetic and follows an autosomal dominant pa...

OBJECTIVE We performed a clinical, functional, and pharmacologic characterization of the novel p.P1158L Nav1.4 mutation identified in a young girl presenting a severe myotonic phenotype. METHODS Wild-type hNav1.4 channel and P1158L mutant were expressed in tsA201 cells for functional and pharmacologic studies using patch-clamp. RESULTS The patient shows pronounced myotonia, slowness of move...