Effect of Intrathecal Anti-Fibroblast Growth Factor-2 Antibodies on the Mechanical Allodynia and Activation of Spinal Cord Astrocytes in Rats.

AIM To investigate the effect of intrathecal anti-fibroblast growth factor-2 (FGF-2) antibodies on the mechanical allodynia and activation of spinal cord astrocytes in a rat model of neuropathic pain. MATERIAL AND METHODS Forty male Sprague-Dawley rats were randomly divided into 4 groups (Each group=10 rats). Group A: Spared nerve injury (SNI) model and intrathecal phosphate-buffered saline (PBS); Group B: SNI model and intrathecal FGF-2 antibodies; Group C: Sham surgery and intrathecal PBS; Group D: Sham surgery and intrathecal basic FGF-2 antibodies. The paw withdrawal mechanical threshold (PWMT) was evaluated one day before the operation and at the 1, 4, 7, 14 and 21 days after the operation. Meanwhile, the expression of FGF-2, glial fibrillary acidic protein (GFAP) of astrocytes, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the L4~6 spinal cord segments were gauged at 21 days after the operation. RESULTS SNI significantly induced the mechanical allodynia and markedly increased the number of FGF-2 and GFAP positive cells and the levels of TNF-α and IL-6 (p < 0.05). Intrathecal injection of FGF-2 antibodies suppressed the increase of FGF-2 and GFAP positive cells, and the levels of TNF-α and IL-6. These antibodies significantly attenuated SNI-induced mechanical allodynia in rats (p < 0.05). CONCLUSION FGF-2 antibodies have the effect of analgesia on neuropathic pain in rats.