Substance P activates NF-kappa B independent of elevations in intracellular calcium in murine macrophages and dendritic cells

Professional antigen presenting cells, such as macrophages, can be activate d by intracellular calcium-dependent as well as calcium-independent mechani sms, depending upon the stimulus used. In this report, we addressed the mec hanism of substance P-induced intracellular signalling in murine macrophage s and dendritic cells. While no increases in intracellular calcium concentr ation were detected in macrophages or dendritic cells using sensitive fluor imetric techniques, substance P did induce rapid enhanced activation of NF- kappa B, a transcriptional activator known to regulate pro-inflammatory cyt okines. These data provide an important mechanism by which substance P may augment the production of pro-inflammatory molecules. (C) 2000 Elsevier Sci ence B.V. All rights reserved.