SLC8A3/NCX3 Proteins and Enzymes

The sodium/calcium exchanger of cardiac sarcolemma rapidly transports calcium during excitation-contraction coupling and is the dominant myocardial calcium efflux mechanism. The sodium/calcium exchanger uses the transmembrane sodium gradient to catalyze countertransport of calcium against its electrochemical gradient in a 3 sodium : 1 calcium exchange. Sodium/calcium exchange activity is present in excitable cells and in non-excitable cells.