Neurotrophin expression in the adult olfactory epithelium.

F. Feron (1) , J. Bianco , I. Ferguson , A. Mackay-Sim

1 NICN - Neurobiologie des interactions cellulaires et neurophysiopathologie - NICN

Published reports of neurotrophin expression in the olfactory system are incomplete because of missing data and conflicting results. Previous studies used a variety of fixation procedures and antibodies on different species and different ages. The aim of the present study was to examine expression of neurotrophins and their receptors using optimized methodologies: five methods of fixation, multiple antibodies, a variety of immunochemical protocols, and RT-PCR. We show here that (i) transcripts for all neurotrophins and their receptors are found in the adult olfactory epithelium; (ii) all neurotrophins are expressed in the supporting cells and the neuronal layers of the undisturbed adult olfactory epithelium while NT4 is found additionally in the horizontal basal cells; (iii) neurotrophin immunoreactivity required a fixative that included parabenzoquinone (not used in previous studies of olfactory tissue); (iv) TrkB and TrkC are restricted to the globose basal cell and neuron layers while TrkA is found in the horizontal basal cells and in the supporting cells where it co-localizes with the low affinity receptor for NGF (p75NTR). These findings confirm that neurotrophins are produced within the olfactory epithelium, suggesting autocrine and paracrine regulation of olfactory neurogenesis.

Domaines: Neurosciences [q-bio.NC]

F. Feron, J. Bianco, I. Ferguson, A. Mackay-Sim. Neurotrophin expression in the adult olfactory epithelium.. Brain Research, 2008, 1196, pp.13-21. ⟨10.1016/j.brainres.2007.12.003⟩. ⟨hal-00320757⟩