Lipoxin A5 (LXA5) is produced by enzymatic transformation of EPA by leukocytes. LXA5 slowly contracts pulmonary parenchymal strips from guinea pig with similar potency to that of LXA4 and LXB4. However, LXA5 does not exert the vasodilatory effects on aortic smooth muscle exhibited by LXA4 and LXB4.