Enzymatic hydrolysis of leukotriene A4 into 5,6-dihydroxy-7,9,11,14-eicosatetraenoic acid and LTB4 by mammalian kidney

Abstract Homogenates from rat and pig kidney converted leukotriene A 4 to 5,6-dihydroxy-7,9,11,14-eicosatetraenoic acid as well as leukotriene B 4 . Both hydrolyses were enzymatic as judged by the effects of heat treatment and proteolytic digestion. Upon subcellular fractionation, conversion of leukotriene A 4 to 5,6-dihydroxy-7,9,11,14-eicosatetraenoic acid occurred both in the 105000xg supernatant and the 20000xg pellet from rat kidney, whereas conversion to leukotriene B 4 was confined to the 105000xg supernatant. We also found production of 5,6-dihydroxy-7,9,11,14-eicosatetraenoic acid and leukotriene B 4 in isolated rat renal epithelial cells, either from exogenous leukotriene A 4 or from this substrate supplied by human leukocytes.