THE EFFECT OF ENDOTHELIN, NEUROPEPTIDE-Y, CALCITONIN-GENE-RELATED PEPTIDE AND SUBSTANCE-P ON NEUTROPHIL FUNCTIONS

Neuropeptides are putative mediators of inflammation. At physiological concentrations substance P has been shown to prime polymorphonuclear neutrophil granulocyte (PMN) chemiluminescence (CL). In the present st udy we show also that both endothelin and neuropeptide Y (NPY), but no t calcitonin gene-related peptide (CGRP) are able to prime PMN oxidati ve metabolism. At similar nanomolar concentrations SP and endothelin ( but not NPY) also primed formyl-methionyl-leucyl-phenylalanine (fMLP)- induced rises of cytosolic calcium. On the other hand, NPY caused a di rect and dose-related increase of cytosolic calcium concentrations. No ne of the mentioned neuropeptides primed PMN aggregation or directly i nduced CL, aggregation or chemotaxis over a wide range of concentratio ns (1 fM-1 muM).