Expression by rat motoneurons of mRNAs for the alpha subunit of the ciliary neurotrophic factor receptor (CNTFR alpha), receptor tyrosine kinase-C (trkC), calcitonin gene-related peptide (CGRP) and galanin was studied by in situ hybridisation, 6d after rat facial nerve transection on postnatal day 1. Similar numbers of motoneurons in both injured and non-injured nuclei hybridised with all probes, despite a reduction in total numbers of motoneurons ipsilaterally. When ciliary neurotrophic factor (CNTF) was applied to the proximal nerve, twice as many motoneurons in the injured nucleus hybridised with the CNTFR alpha probe ipsilaterally compared to the non-injured nucleus, while motoneuronal loss was not evident. These results indicate that survival of motoneurons after neonatal axotomy and CNTF treatment is associated with increased CNTF receptor alpha expression.
- Ciliary neurotrophic factor receptor
- In situ hybridisation