TrkA expression in olfactory epithelium and bulb during development

THE purpose of the present study was to examine immunohistochemically the e xpression of high-affinity nerve growth factor receptor (trkA) in the olfac tory nervous system of developing mice and of colchicine-treated adult mice . Olfactory epithelia of embryos and neonates showed trkA immunoreactivity not only in basal cells but in receptor cells, with trkA-immunoreactive olf actory nerve fibers in the subepithelium and the bulb. In adults, trkA immu noreactivity was found only in basal cells of olfactory epithelia. Olfactor y epithelia of colchicine-treated adult mice, however, exhibited appearance of trkA-immunoreactive receptor cells and increased trkA immunoreactivity in olfactory nerve fibers. These findings indicate that expression of trkA continually occurs in the olfactory nervous system during life and that trk A can be highly expressed during development. NeuroReport 10:2205-2208 (C) 1999 Lippincott Williams & Wilkins.