Antagonism between calcium and sodium ions.
D002118:Calcium / Q000378:metabolism*; D006321:Heart / Q000502:physiology*; D006801:Humans; D007477:Ions; D012964:Sodium / Q000378:metabolism*; D014882:Water-Electrolyte Balance
D007477:Ions; D012964:Sodium; D002118:Calcium
CALCIUM/metabolism; HEART/physiology; SODIUM/metabolism