Structure and Regulation of the Amiloride-Sensitive Epithelial Sodium Channel

摘要: In high-resistance epithelia such as distal segments of the kidney tubule, colon, urinary bladder, skin, or airways, coupling passive electrodiffusion sodium through apical membrane with active extrusion intracellular by Na+/K+/ATPases present in basolateral generates Na+ reabsorption via a transcellular pathway (Palmer, 1992; Eaton and Hamilton, 1988; Garty Benos, 1986). The rate-limiting factor for epithelial lining is formed an channel that can be blocked diuretic molecules triamterene amiloride (Eigler Crabbe, 1969). Different hormones control activity this channel. For instance, aldosterone regulates balance, blood volume, pressure stimulating colon (Garty 1986; Rossier Palmer, 1992); similarly, glucocorticoids increase lung, thereby regulating amount respiratory fluid (O’Brodovich, 1991; Champigny et al., 1994). these different tissues, represents major component total ionic permeability membrane.