kidney lipid composition measurement kidney 20-HETE level 2013-11-04T17:22:56Z JSmith The amount of 20-hydroxyeicosatetraenoic acid, a vasoconstrictor that consists of arachidonic acid (a C20, polyunsaturated fatty acid having four (Z)-double bonds at positions 5, 8, 11 and 14) bearing a hydroxy substituent at position 20, in a specified sample of kidney tissue, that is, tissue from one or both of the paired organs which function to maintain proper water and electrolyte balance, regulate acid-base concentration, and filter the blood of metabolic wastes. kidney 20-hydroxyeicosatetraenoic acid level