Although
methylprednisolone (MP) is the standard of care in acute
spinal cord injury (SCI), its functional outcome varies in clinical situation. Recent report demonstrated that MP depresses the expression of growth-promoting
neurotrophic factors after acute SCI. The present study was designed to investigate whether continuous infusion of
brain-derived neurotrophic factor (
BDNF) after MP treatment promotes functional recovery in severe SCI.
Contusion injury was produced at the T10 vertebral level of the spinal cord in adult rats. The rats received MP intravenously immediately after the injury and
BDNF was infused intrathecally using an osmotic mini-pump for six weeks. Immunohistochemical methods were used to detect ED-1, Growth associated protein-43 (GAP-43), neurofilament (NF), and
choline acethyl
transferase (ChAT) levels.
BDNF did not alter the effect of MP on hematogenous inflammatory cellular infiltration. MP treatment with
BDNF infusion resulted in greater axonal survival and regeneration compared to MP treatment alone, as indicated by increases in NF and
GAP-43 gene expression. Adjunctive
BDNF infusion resulted in better locomotor test scores using the Basso-Beattie-Bresnahan (BBB) test. This study demonstrated that continuous infusion of
BDNF after initial MP treatment improved functional recovery after severe
spinal cord injury without dampening the acute effect of MP.