THE EFFECTS OF TACHYKININS ON INFLAMMATORY AND IMMUNE CELLS

The aim of this article is to provide an up-dated overview of the avai lable information on the role played by tachykinins in recruiting/regu lating the function of immune/inflammatory cells, an issue which has r eceived considerable input from the recent availability of potent and selective antagonists for tachykinin receptors. It appears that NK1 re ceptors play a role in mediating the extravascular migration of granul ocytes into inflamed tissues in response to various inflammatory stimu li, although this effect may not be due to the expression of NK1 recep tors by granulocytes themselves. Several data also imply a role for NK 1 and NK2 receptors in regulating immune function. No data are availab le to suggest the expression of NK3 receptors by inflammatory/immune c ells. Mast cell degranulation by substance P appears to be a non-recep tor dependent response which may take place in vivo during intense sti mulation. An emerging concept in the field relates to the ability of c ertain immune cell types to synthesize and possibly release tachykinin s. immune cells could represent an additional source of tachykinins in inflamed tissues, providing a non-neurogenic tachykininergic contribu tion to the local inflammatory process. (C) 1997 Elsevier Science B.V.