N-acetyl-leukotriene E4 is a potent constrictor of rat mesenteric vessels

N-Acetyl-leukotriene E4 administered to conscious freely moving rats produced a dose-dependent vasoconstriction in the mesenteric vessels which led to profound reduction of blood flow to the gut. Renal and hindquarter blood flow and vascular resistance were not affected even by high doses of N-Acetyl-leukotriene E4. N-Acetyl-leukotriene E4 was 10-fold more potent than the thromboxane analog U-46619 and 1000-fold more potent than prostaglandin F2 alpha but 2-5-fold less potent than leukotriene D4/E4 to induce mesenteric vasoconstriction. These data indicate that N-acetyl-leukotriene E4 is a biologically active metabolite of peptide leukotrienes, and might play a role in cardiovascular derangements mediated by leukotrienes.