Abstract:

Objective    To investigate the effect of intrathecal administration of vascular endothelial growth factor (VEGF) on repair of spinal cord injury（SCI）, and explore neuroprotection of VEGF on neurons and nerve fibers. Methods    45 animals were randomly divided into three groups. VEGF was intrathecally administrated at a dose of 25ng twice a day for a week in the VEGF group after SCI. The Basso， Beattie and Bresnahan locomotor rating scale (BBB) was observed each week． 8 weeks later, histological changes were examined by hematoxyhn and eosin (HE), immunohistochemical staining and an electron microscope. Results     The BBB scale in the VEGF group was higher than that in the model group， especially at the last 4 weeks. Histology revealed that the morphology of fibers and neurons at the ventral of the spinal cord in the VEGF group was better than those in the model group. More vessels were observed in animals administrated with VEGF compared with the model group(P<0.001）. The number of caspsase-3-positive cells in the VEGF group was smaller（P<0.001）. Slightly damaged nerve fibers and neurons were found in the VEGF group, with fewer mitochondria with disrupted cristae and secondary lysosomes were fewer compared with the model group． Conclusions     Administration of VEGF improves part of the functions of nerve fibers and provides neuroprotection for damaged neurons and fibers.

Key words: Intrathecal administration; Vascular endothelial growth factor； Spinal cord injury； Caspase3; Ultrastructure