Pathobiology of visceral pain: Molecular mechanisms and theraputic implications - I. Cellular and molecular biology of sodium channel beta-subunits: therapeutic implications for pain?

Voltage-gated sodium channel alpha-subunits have been shown to be key media tors of the pathophysiology of pain. The present review considers the role of sodium channel auxiliary beta-subunits in channel modulation, channel pr otein expression levels, and interactions with extracellular matrix and cyt oskeletal signaling molecules. Although beta-subunits have not yet been dir ectly implicated in pain mechanisms, their intimate association with and ab ility to regulate alpha-subunits predicts that they may be a viable target for therapeutic intervention in the future. It is proposed that multifuncti onal sodium channel beta-subunits provide a critical link between extracell ular and intracellular signaling molecules and thus have the ability to fin e tune channel activity and electrical excitability.