Collecting Duct Cells (CD)

In humans, the cortical collecting duct contains a high-resistance epithelium comprised of two cell types. Principal cells are the main Na+ reabsorbing cells and the site of action of aldosterone, K+-sparing diuretics, and spironolactone. Type A and B intercalated cells make up the second cell type in the collecting duct epithelium. Type A intercalated cells mediate acid secretion and bicarbonate reabsorption. Type B intercalated cells mediate bicarbonate secretion and acid reabsorption.