Na⁺/Ca²⁺ Exchanger

The Na⁺/Ca²⁺ exchanger (NCX) is a low affinity, high capacitance calcium antiporter membrane protein that functions to regulate intracellular calcium concentrations. It is located on the plasma, mitochondrial and endoplasmic reticular membranes of excitable cells. Using the electrochemical gradient of Na⁺, one Ca²⁺ ion is transported out of the cell in exchange for three Na⁺ ions.

The Na⁺/Ca²⁺ exchanger compliments the high affinity, low capacitance Ca²⁺-ATPase and together, they are involved in a variety of cellular functions including control of neurosecretion, relaxation of cardiac muscle, maintenance of intracellular Ca²⁺ stores in the endoplasmic and sarcoplasmic reticuli and excitation-contraction coupling. Under normal physiological conditions, Na⁺/Ca²⁺ exchangers export Ca⁺ from the cell. However, under cellular stress, such as excitotoxicity, they can switch to 'reverse mode,' which has a protective effect.

External sources of pharmacological information for Na⁺/Ca²⁺ Exchanger :

• BJP Guide

Na⁺/Ca²⁺ Exchanger Gene Data