Metabolism of leukotriene A4 by human erythrocytes. A novel cellular source of leukotriene B4.

摘要: Human erythrocytes transformed leukotriene A4 into B4. Metabolism was proportional to the erythrocyte concentration, even at subphysiological levels (0.08-4 X 10(9) erythrocytes/ml). Comparative metabolic studies excluded possibility that B4 originated from trace amounts of polymorphonuclear leukocytes or platelets present in purified suspensions. For example, suspensions isolated (100-500 10(6) cells/ml) failed convert B4; and conversion by neutrophils insufficient account for formed erythrocytes. Leukotriene formation maximal within 2 min substrate concentration dependent. Enzymatic activity a 56 degrees C labile nondialyzable (Mr greater than 30,000) soluble component 100,000 g supernatant obtained lysed In contrast contemporary view, our results indicate human are not metabolically inert terms eicosanoid biosynthesis. The role during inflammatory pulmonary disorders deserves re-examination this context.