Galanin expression in sensory neurons after nerve compression or transection

Galanin is probably involved in nociceptive sensory processing in spinal cord. We investigated whether a common injury, peripheral nerve compression, induced up-regulation of galanin (immunocytochemistry) in sensory neurons in rats 6 or 14 days post-injury and compared the response with other nerve injuries. Sciatic nerve compression increased the number of galanin positive sensory neurons as compared to uninjured and contralateral dorsal root ganglia. Complete transection was more efficient than a partial transection and a slight compression injury as an inducer of galanin. Mainly small diameter sensory neurons became positive but also some large diameter neurons. We conclude that nerve compression up-regulates galanin in sensory neurons. The extent of the induction could be related to the severity of nerve injury.