Structure and function of cardiac sodium and potassium channels.
The application of patch-clamp and molecular approaches has resulted in an increasingly refined understanding of the molecular entities underlying cardiac sodium and potassium currents. The sodium current results from expression of a single large alpha-subunit, whereas multiple potassium currents and potassium channel alpha-subunits have been identified. Recapitulation of some ion currents in heterologous expression systems requires not only expression of alpha-subunits but also ancillary (beta) subunits. Domains common to functions such as activation, inactivation, and drug block are now being identified in alpha- and beta-gene products. Variability in the expression or function of individual ion-channel genes is an increasingly recognized source of variability in the ion currents recorded in heart cells under physiological conditions (e.g. during development) as well as in disease.
Roden
D M
DM
Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-6602, USA.
George
A L
AL
D000818:Animals; D004594:Electrophysiology; D006801:Humans; D009206:Myocardium / Q000378:metabolism*; D015221:Potassium Channels / Q000235:genetics* / Q000502:physiology*; D015222:Sodium Channels / Q000235:genetics* / Q000502:physiology*; D013329:Structure-Activity Relationship
D015221:Potassium Channels; D015222:Sodium Channels