Enables sodium:proton antiporter activity. Involved in several processes, including regulation of pH; response to glucocorticoid; and sodium ion transport. Located in apical plasma membrane and brush border membrane. Used to study hypertension. Biomarker of obesity and renovascular hypertension. Human ortholog(s) of this gene implicated in congenital secretory sodium diarrhea 8. Orthologous to human SLC9A3 (solute carrier family 9 member A3). [provided by Alliance of Genome Resources, Apr 2022]