WHEN macrophages encounter inflammatory stimuli either in vivo or in vitro, they respond by releasing a number of products which may account for the central role that this cell has in chronic inflammatory diseases1. These products include hydrolytic enzymes active at neutral2 or acidic pH (ref. 1), components of both the classical3 and alternate pathway4 of complement, factors modulating responses of lymphocytes to antigens and mitogens5, and factor(s) influencing the proliferation6 and synthesis of collagen7 by fibroblasts. We now show that macrophages whose phospholipid components were labelled with 3H-arachidonic acid also synthesise and release 3H- prostaglandins (PGs) in response to inflammatory stimuli. These observations are consistent with the findings that human macrophages on intrauterine devices8 and guinea pig macrophages responding to lymphokines 9 release PGs.
ASJC Scopus subject areas