Increased expression of Na
1.3 mRNA in DRG neurons following SNL injury. (A) Autoradiographic in situ hybridization data showing increased levels of Nav1.3 mRNA in rat DRG neurons from 2 to 42 days after neuropathic injury. Arrows indicate the lumbar DRG level ipsilateral to the SNL injury. Note that the increase in Nav1.3 mRNA occurs in the ipsilateral (injured) L5 and L6 DRGs, but remains unchanged in (uninjured) L4 DRG and sham DRGs. Sham DRGs represent the 14 day post-injury time point. (B) High magnification (40×) images of emulsion-dipped sections showing increased Nav1.3 mRNA expression in cell bodies of small diameter DRG neurons (arrows) on the ipsilateral side of the nerve injury. Scale bar, 50 μm.