The Na+/HCO₃- cotransporter family is a group of transmembrane proteins responsible for the cotransport of sodium ions and bicarbonate ions into and out of cells. The main family members include NBCe1, NBCe2, and NBCn1, which consist of multiple transmembrane domains and are mainly located in the cell membrane of tissues such as the kidney, pancreas, and eyes. These cotransporters are involved in regulating acid-base balance, cell volume, and electrolyte transport by maintaining the balance of ion concentrations inside and outside the cell, affecting cell function and survival. The expression of Na+/HCO₃- cotransporter family members is tissue- and cell-specific, and mutations or dysregulation of their genes are associated with various diseases, including renal tubular acidosis, hypertension, and pancreatic dysfunction.