ANALYSIS OF CUTANEOUS SENSORY NEURONS IN TRANSGENIC MICE LACKING THE LOW-AFFINITY NEUROTROPHIN RECEPTOR P75

Citation
I. Bergmann et al., ANALYSIS OF CUTANEOUS SENSORY NEURONS IN TRANSGENIC MICE LACKING THE LOW-AFFINITY NEUROTROPHIN RECEPTOR P75, European journal of neuroscience, 9(1), 1997, pp. 18-28
Citations number
58
Categorie Soggetti
Neurosciences
ISSN journal
0953816X
Volume
9
Issue
1
Year of publication
1997
Pages
18 - 28
Database
ISI
SICI code
0953-816X(1997)9:1<18:AOCSNI>2.0.ZU;2-Y
Abstract
Mice with a targeted mutation of the p75 low affinity neurotrophin rec eptor display smaller peripheral nerves and dorsal root ganglia. Here we show that transgenic mice have a significant elevation of threshold s to noxious mechanical and heat stimuli compared with p75+/+ control mice. Immunocytochemical analysis using antibodies against PGP 9.5 (a panaxonal marker) and calcitonin gene related peptide (CGRP, which lab els peptidergic neurons) showed a reduction to 73% and 54%, respective ly, of the epidermal innervation density. However, analysis of the cel l size distribution of toluidine blue-stained dorsal root ganglia show ed no selective loss of neurons of particular diameters. Moreover, the neurochemical profile of dorsal root ganglia cells as defined by trkA , CGRP, IB4 and RT97 immunostaining revealed no significant difference s in comparison with p75+/+ animals. Staining of the dorsal horn of th e spinal cord for CGRP and IB4 was also normal in p75-/- animals. Taki ng into account a previously reported loss of similar to-50% dorsal ro ot ganglion neurons, we conclude that all types of sensory neurons are equally depleted in p75-/- mice and that the absence of p75 impedes t he development of more than one neuronal subtype.