Abstract: Objective To investigate the mechanisms of basic fibroblast growth factor( bFGF) promoting blood spinal cord barrier(BSCB) recovery in rats with spinal cord injury（SCI）．Methods Rats were randomly divided into sham group， SCI model group， bFGF intervention group( 80 μg/kg ). The nerve function of hind limb motor was evaluated by Basso, Beattie, and Bresnahan ( BBB) scores during the 14 days postoperative period．Neuron loss of injured spinal cords were observed by haematoxylin and eosin( HE) staining and NeuN staining．The integrity of BSCB was investigated with Evan’s Blue dye and fluorescein isothiocyanate (FITC)–dextran extravasation. The expression protein of adhesive connection protein (p120 - catenin, β- catenin) and tight junction protein expression (occludin, claudin - 5) were analysised by Western blot． Results Compared with SCI model group, bFGF intervention group neuron loss decreased significantly at 3d after injury（P<0.05）; the permeability of blood spinal cord barrier was found obviously reduced at 1d after injury; the expressions of p120 - catenin, beta - catenin, occludin, claudin - 5 protein of bFGF intervention group were increased dramatically at 1d after injury（P<0.05）. Conclusion bFGF improves the recovery of BSCB in an SCI model by reducing the loss of neurons and increasing the expressions of adhesion junction proteins and tight juction proteins.

Key words: basic fibroblast growth factor, spinal cord injury, adhesive connection protein, tight junction protein expression, blood spinal cord barrier