Decreased spinal alpha2a- and alpha2c-adrenergic receptor subtype mRNA in a rat model of neuropathic pain

Abstract

Northern blot analyses performed on the lumbar spinal cords (L4-L6) of rats with the Bennett and Xie chronic constriction injury (CCI) nerve ligation model of neuropathic pain were compared to non-ligation surgery and unoperated control rats to determine if there is a change in alpha2-adrenergic receptor mRNA expression with neuropathic pain. Compared to unoperated rats, CCI rats had bilaterally lower RG-20 mRNA, corresponding to the alpha2A-adrenergic receptor subtype (affected 62.4 +/- 22.1% and contralateral 69.5 +/- 16.6% of unoperated, P<0.05), and RG-10 mRNA, corresponding to the alpha2C-adrenergic receptor subtype (affected 49.2 +/- 19.1% and contralateral 50.0 +/- 14.4% of unoperated, P<0.05). These results would suggest a corresponding decrease in alpha2A- and alpha2C-adrenergic receptor concentrations in the CCI and non-ligation surgery rats' spinal cords.