| Objective: To explore the changes in the expression of basic fibroblast growthfactor (bFGF) and mRNA in the spinal cord of adult rats following cord transectioninjury.Method: 50 SD adult rats were randomly divided into five groups (n=10 in eachgroup): the sham-operation group, cord transection injury (the spinal cord transectionbetween T13-L1 segments) 3d, 7d, 14d and 21d group. Every five rats of each groupwere used for immunohistochemistry (n=5 in each) and RT-PCR (n=5 in each)respectively. BBB (Basso, Beattie, Bresnahan) score, somatosensory evokedpotentials (SEP) technique were adopted to assess the locomotor and sensoryfunctional revival of animals for 3d, 7d, 14d and 21d post operation (dpo). Spinal cordsegments were used for immunohistochemical ABC staining and reverse transcriptionpolymerase chain reaction (RT-PCR) technique, respectively. Localization and thecounting of the positive cells for bFGF were observed at the ventral horn, dorsal hornand laminaⅧ,Ⅸof spinal cord following transection injury in the spinal cord of adultrats under microscope. Densitometric analysis was performed using Bio-GelImagining system.β-actin was amplified as an internal control. Datas were analyzedby one-way ANOVA and LSD-q test.Result: (1). The evaluation of BBB score showed: both hindlimbs in theexperimental group at 3dpo was zero after transection injury. Then it increaseddramatically to 0.78±0.25 at 7 dpo, registered 2.41±0.72 at 14 dpo, and it was3.55±0.50 at 21 dpo. The statistical analysis for the BBB scores showed a significantdifference from each other (p＜0.05). (2). No SEP could be recorded throughout theexperimental period. (3). The immunohistochemistry result showed: at the caudal stump near injury site, the number of positive neuron for bFGF markedly increased at7dpo in the ventral horn and laminaⅧ,Ⅸ, and reached a peak. It was sustaind to21dpo and more than the sham-operation level. The number of positive neuron forbFGF in the dorsal horn markedly lower than the sham-operation group from 3d to21d after transection injury, comparing with the ventral horn. (4). RT-PCR showed:The level of bFGFmRNA was significantly increased at 3dpo, when compared withthe sham-operation group, then come back to sham-operation level at 14dpo, till21dpo.Conclusion: (1). The movement function of hindlimbs scoring showed that partlyimproved markedly from 7 dpo to 21dpo, but no changes for sensory function. (2). Atthe caudal stump, the number of positive neurons for bFGF markedly increased at7dpo and reached a peak in the ventral horn and laminaⅧ,Ⅸ. It was sustaind 21 dpoand more than the sham-operation level. At the caudal stump, the level of bFGFmRNA was significantly increased at 3dpo, and come back to sham-operation level at14dpo. All data indicated endogenous bFGF expression could be involved in theplasticity of the spinal cord following transection injury.
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