Cerebral dura mater and cephalalgia: relationships between mast cells and catecholaminergic nerve fibers in the rat.

The aim of the present study was to examine whether mast cells have the same variations as the related catecholaminergic nerve fibers. Chemical sympathectomy or surgical removal of right superior cervical ganglion induced a rapid decrease of fluorescence in both nerve fibers and mast cells, as confirmed by quantitative analysis (nerve fibers 19 +/- 1.1 vs 1.3 +/- 0.6; mast cell 10.8 +/- 1.9 vs 2.1 +/- 0.3). The results of quantitative analysis after nerve fiber stimulation (electrical), however, showed an increase of the fluorescence in both the nerve fibers and the mast cells (nerve fibers 43.4 +/- 2.4; mast cells 18.6 +/- 1.6). Moreover, we found that the basal zone is more innervated (regarding catecholaminergic nerve fibers) than the apical one, and that the fluorescence level decreases passing from the vasal zone to the perivasal and intervasal zones. Further studies are needed in order to clarify the role of fluorescent nerve fibers and mast cells of cerebral dura mater in cephalalgia.