Voltage-gated sodium channels (VGSCs) consist of a pore-forming α-subunit and regulatory β-subunits. Several families of neuroactive peptides of Conus snails target VGSCs, including μO-conotoxins and μ-conotoxins. Unlike μ-conotoxins and the guanidinium alkaloid saxitoxin (STX), which are pore blockers, μO-conotoxins MrVIA and MrVIB inhibit VGSCs by modifying channel gating. μO-MrVIA/B can bloc...

BACKGROUND Reduced motor and sensory nerve amplitudes in critical illness polyneuropathy (CIP) are characteristic features described in electrophysiological studies and due to dysfunction of voltage-gated sodium channels. Yet, faulty membrane depolarization as reported in various tissues of critically ill patients may cause reduced membrane excitability as well. The aim of this study was to com...

Voltage-gated sodium channels initiate action potentials in nerve, muscle, and other electrically excitable cells. Voltage-gated calcium channels are activated by depolarization during action potentials, and calcium influx through them is the key second messenger of electrical signaling, initiating secretion, contraction, neurotransmission, gene transcription, and many other intracellular proce...

A variety of inherited human disorders affecting skeletal muscle contraction, heart rhythm, and nervous system function have been traced to mutations in genes encoding voltage-gated sodium channels. Clinical severity among these conditions ranges from mild or even latent disease to life-threatening or incapacitating conditions. The sodium channelopathies were among the first recognized ion chan...

Five inherited human disorders affecting skeletal muscle contraction have been traced to mutations in the gene encoding the voltage-gated sodium channel Na(v)1.4. The main symptoms of these disorders are myotonia or periodic paralysis caused by changes in skeletal muscle fiber excitability. Symptoms of these disorders vary from mild or latent disease to incapacitating or even death in severe ca...

Isom, Lori L. Pathobiology of Visceral Pain: Molecular Mechanisms and Theraputic Implications. I. Cellular and molecular biology of sodium channel b-subunits: therapeutic implications for pain? Am. J. Physiol. Gastrointest. Liver Physiol. 278: G349–G353, 2000.—Voltage-gated sodium channel a-subunits have been shown to be key mediators of the pathophysiology of pain. The present review considers...

AIM To investigate the mechanism of agmatine by observing the effect of agmatine on the voltage-gated channels in rat hippocampal neurons. METHODS The whole-cell patch recording technique was performed to record the voltage-gated potassium, sodium, and calcium currents in cultured rat hippocampus. Agmatine was applied directly to the single neuron using a pressure injector with microtubules. ...

Human studies have firmly implicated voltage-gated sodium channels in human pain disorders, and targeted and massively parallel genomic sequencing is beginning to be used in clinical practice to determine which sodium channel variants are involved. Missense substitutions of SCN9A, the gene encoding sodium channel NaV1.7, SCN10A, the gene encoding sodium channel NaV1.8, and SCN11A, the gene enco...

The properties and distribution of voltage-gated ion channels contribute to electrical signaling in neuronal dendrites. The apical dendrites of CA1 pyramidal neurons in hippocampus express a wide variety of sodium, calcium, potassium, and other voltage-gated channels. In this report, we provide some new evidence for the role of the delayedrectifier K channel in shaping the dendritic action pote...