Galanin-mediated control of pain: enhanced role after nerve injury

Galanin is a neuropeptide which inhibits sensory transmission and occurs in cells of the dorsal root ganglion and spinal chord interneurons. The effects of a galanin receptor antagonist, M-35, on flexor reflex excitability in intrathecally injected rats with intact and sectioned sciatic nerves was studied. The results showed that M-35 exerts a facilitatory effect on flexor reflex excitability by activating C-fibers. M-35 potentiated condition stimulation-induced reflex facilitation. Chronic infusion of M-35 resulted in enhanced autotomy behavior. The results suggest that galanin and galanin receptor agonists may be potential analgesic agents.