Evidence for serotonin influencing the thalamic infiltration of mast cells in rat.
Serotonin (5-HT) is involved in neuroimmunomodulation. We analyzed the effects of sumatriptan, a 5-HT(1B/1D) receptor agonist, and ondansetron, a 5-HT(3) receptor antagonist, on thalamic mast cell (TMC) population, the only immunocytes known to infiltrate the brain in physiological conditions. Only sumatriptan was effective, significantly increasing TMC numbers versus controls, and especially those containing 5-HT. 5-HT(1B) receptors are concentrated in the median eminence on non-serotonergic axonal endings, probably hypothalamic terminal fibers, involved in hypothalamic-pituitary neuroendocrine modulating processes. TMC variations could reflect serotonergic actions on these fibers. TMCs would thus be cellular interfaces mediating immune action in the nervous system in relation with the hormonal status of the organism.
Dubayle
D
D
CNRS UMR 8119 Neurophysique et physiologie, Université René Descartes, UFR Biomédicale, 45 rue des Saints-Pères, 75270 Paris Cedex 06, France. david.dubayle@univ-paris5.fr
Servière
J
J
Menétrey
D
D
D000818:Animals; D015550:Cell Degranulation / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology*; D004027:Diencephalon / Q000737:chemistry / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D007150:Immunohistochemistry; D008297:Male; D008407:Mast Cells / Q000737:chemistry / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D036641:Microscopy, Fluorescence, Multiphoton; D017294:Ondansetron / Q000008:administration & dosage; D051381:Rats; D017207:Rats, Sprague-Dawley; D044302:Receptor, Serotonin, 5-HT1B / Q000032:analysis; D012701:Serotonin / Q000032:analysis / Q000502:physiology*; D058825:Serotonin 5-HT1 Receptor Agonists; D018170:Sumatriptan / Q000008:administration & dosage; D013788:Thalamus / Q000737:chemistry / Q000166:cytology* / Q000502:physiology*
D044302:Receptor, Serotonin, 5-HT1B; D058825:Serotonin 5-HT1 Receptor Agonists; D012701:Serotonin; D017294:Ondansetron; D018170:Sumatriptan