Journal of Neuroscience, Vol 5, 2382-2387, Copyright © 1985 by Society for Neuroscience
Monoclonal antibodies reveal novel aspects of the biochemistry and organization of olfactory neurons following unilateral olfactory bulbectomy
JL Hempstead and JI Morgan
Following unilateral olfactory bulbectomy in rats the ipsilateral olfactory
neuroepithelium undergoes degeneration. Subsequently, the receptor neuron
complement of the tissue is restored by the proliferation and
differentiation of immature neuroblasts. However, as noted by other
workers, in the absence of a target organ the dynamics of neuron
regeneration is altered such that there is an overall reduction in the
number of cells positive for the olfactory marker protein when cellular
equilibrium is re-established. Immunocytochemical staining of the olfactory
epithelium of unilaterally bulbectomized rats with a series of
anti-neuronal monoclonal antibodies reveals an attenuation of binding of
some antibodies to the neurons of the ipsilateral epithelium. In contrast,
other anti-neuronal monoclonal antibodies show no difference in staining
intensity when ipsilateral and control contralateral epithelia are
compared. These data suggest that the expression of some neuronal antigens
is subject to control by the target olfactory bulb, whereas others are
independent of such putative regulation. Besides altering the expression of
some antigenic determinants, olfactory bulbectomy also results in certain
organizational changes in epithelium. First, bulbectomy produces an
increase in the incidence of a cell type that appears to span the
neuroepithelium. Although the morphology of these cells is more akin to a
sustentacular cell than to a receptor neuron, they are not immunoreactive
with antibodies to sustentacular cells. The cells are stained, however, by
an anti-neuronal antibody, NEU-9. The second aspect of altered organization
is the appearance of novel olfactory marker protein-positive structures in
the olfactory mucosa.(ABSTRACT TRUNCATED AT 250 WORDS)