Cutaneous reactions to intradermal prostaglandins

Summary 1 The effects of intradermally injected prostaglandins (PGs) E1, E2, F1α and F2α have been examined in the rat and in man. 2 PGE1 and PGE2 caused an increase in local vascular permeability in rat skin; their potency was comparable with that of other putative mediators of inflammation (histamine, bradykinin, and 5 ‐hydroxytryptamine), but PGF1α and PGF2α were only slightly active even at a dose of 1 μg. 3 Prior administration of mepyramine and methysergide, or depletion of skin mast cell amines with compound 48/80, indicated that PGE2 exerted its permeability effect in the rat by a release of mast cell amines. 4 Nanogramme doses of PGE1 and PGE2 or microgramme doses of PGF1α and PGF2α injected intradermally into the human forearm induced weal and flare responses. 5 It is concluded that prostaglandins E1 and E2 can act as intermediates in the production of hyperaemia and oedema resulting from cell damage in the rat and man.