The role of interleukin-6 in incisional pain in the rats / 中国医师杂志

ABSTRACT

Objective To investigate the expression of interleukin-6 (IL-6) and its role in incisional pain in the rat model.Methods Incisional pain rat model was established by a longitudinal incision in right plantar hind paw of isoflurane-anesthetized rats.Spinal cords were removed at various postoperative times (1,6,24,72 h).The gene expression of IL-6 in the spinal cord was determined by a Real-time PCR.Immunohistochemistry and double-labeling immunofluorescence were performed to determine the expression of IL-6 after incision.Intrathecal injection of IL-6 antibodies was performed to modulate the spinal IL-6 after surgical incision,and the mechanical hypersensitivity was assessed by paw withdrawal thresholds from mechanical stimuli of von Frey filaments.Results After hind-paw incision,the IL-6 mRNA level was upregulated in the ipsilatcral lumbar spinal cord.The immunoreactivity of IL-6 in spinal cord was increased after hind-paw incision at 6 hours after incision.The upregulated spinal IL-6 was mainly localized in the neurons and endothelial cells.Intrathecal injection of IL-6 antibodies dramatically inhibited the surgical incision that evoked pain hypersensitivity.Conclusions The present study showed that the upregulated IL-6 in the spinal cord contributed to the pain hypersensitivity after surgical incision,inhibiting the upregulated IL-6 in the spinal cord may be a possible new therapeutic target for the treatment of postoperative pain.