Leukotrienes as mediators of skin inflammation

Leukotrienes (LTs) derived from the 5‐lipoxygenase pathways of arachidonic acid metabolism, are a new group of biologically active mediators. LTC4, LTD4 and LTE4 are considered collectively to account for the activity of slow reacting substance of anaphylaxis (SRS‐A). They have potent smooth muscle contracting activity (Drazen et al., 1980; Holme et al., 1980) and cause vascular permeability changes in guinea‐pig skin (Peck, Piper & Williams, 1981). LTB4 has been shown to be a potent chemotactic and chemokinetic agent for polymorphonuclear leucocytes (PMNs) (Ford‐Hutchinson et al., 1980; Smith, Ford‐Hutchinson & Bray, 1980) and to cause vascular permeability changes in rabbit, rat and guinea‐pig skin (Bray et al., 1981a). In human skin LTB4 has been shown to be a chemotactic agent for neutrophils (Bray, Ford‐Hutchinson & Smith, 1981b; Camp et al., 1982). LTC4 and LTD4 have pronounced inflammatory actions in human skin causing weal and flare responses and increases in blood flow at low concentrations (Camp et al., 1982; Bisgard, Kristensen & Sondergaard, 1982). The present studies were designed to investigate a variety of leukotrienes on permeability responses in rabbit and guinea‐pig skin.