The Change Of P-CREB After Surgical Incisicnal Pain In Rat Spinal Cord

Objective: The cAMP response element binding protein plays an important role in pathological pain and inflammatory pain. But the pathogenic role of CREB in the incisional pain is not clear. The present study aims to explore the role of phosphorylation of CREB in the incision-induced pain hypersensitivity.Method: A longitudinal incision was made in one plantar hind paw of isoflurane-anesthetized rats. Spinal cords were removed at various postoperative times after behave test (0.5 - 24 h). The phosphorylation of CREB was determined by immunohistochemistry and double-labeling immunofluorescence. Intraperitoneal injection of Morphine and Gabapentin was used to determine the interaction between phosphorylation of CREB and Morphine and Gabapentin. Results: After hind-paw incision, the phosphorylation of CREB was enhanced in the ipsilateral lumbar spinal cord (P<0.05). The enhancing of p-CREB was mainly in the neurons which were in the dorsal horn of spinal cord. All these were shown by using double-labeling technique and p-CREB was mainly in the neurons. Intraperitoneal injection of Morphine prevented the increased phosphorylation of CREB in spinal cord and inhibited the mechanical allodynia induced by incision (P>0.05). Gabapentin didn't inhibit the phosphorylation of CREB (P<0.05) but inhibited the mechanical allodynia partly.Conclusion: The present studies show that incision induced the phosphorylation of CREB in spinal cord, and the increase of p-CREB is mainly in the neurons. The phosphorylation of CREB in spinal cord can contribute to the pain hypersensitivity induced by surgical incision.