MODULATION OF NEUROPATHIC PAIN IN RATS BY INTRATHECALLY INJECTED SEROTONERGIC AGONISTS

THE involvement of spinal cord serotonergic influences in the developm ent of autotomy, a proposed behavioural model of denervation pain, was studied in rats subjected to sciatic and saphenous nerve transection 5 min after intrathecal injection of 100 or 200 mu g of several seroto nergic receptor subtype agonists. Injection of 8-OH-DPAT, m-CPP, 2-m-5 -HT and a low dose of 5-HT, significantly shifted one or more of the p arameters describing autotomy to less intense behaviour. In contrast, the injection of CGS-12066B and DOI intensified autotomy. These result s suggest both a modulatory role for spinal cord serotonin in the even ts occurring shortly after neurectomy and new therapeutic approaches f or the prevention of certain pain syndromes, such as phantom limb pain .