Peripherin and ATF3 genes are differentially regulated in regenerating and non-regenerating primary sensory neurons

Peripheral nerve injury leads to deficient recovery of sensation and a causative factor may be that only 50-60% of primary sensory neurons succeed in regenerating axons after primary nerve repair. In this study, an in vivo rat sciatic nerve injury and regeneration model was combined with laser microdissection and quantitative real-time polymerase chain reaction with the aim of examining the gene expression of regenerative molecules in cutaneous and muscular sensory neurons. Recent studies have identified peripherin and ATF-3 molecules as crucial for neurite outgrowth propagation; our novel findings demonstrate a subpopulation of non-regenerating sensory neurons characterized by a failure to upregulate transcription of these molecules and that a greater peripherin mRNA expression in injured cutaneous neurons may potentiate this subpopulation to regenerate more axons than muscle afferent neurons following injury. The gene expression of the structural neurofilament NF-H is found to be significantly downregulated following injury in both sensory subpopulations. (C) 2009 Elsevier B.V. All rights reserved.