Effect of MK801 on neurotrophin expression. Spinal cord sections were processed at 24 h after SCI to determine the levels for BDNF and GDNF by western blot analysis. A basal level of BDNF and GDNF were detected in the spinal cord from Sham-operated animals, whereas BDNF and GDNF levels were substantially reduced in SCI mice (a, a1 and b, b1). MK801 MK801 (2 mg/kg 30 min and 6 h after SCI induction) treatment significantly blunted SCI-induced reduction of BDNF, while showed a trend of increase for GDNF (a, a1 and b, b1). The relative expression of the protein band was standardized for densitometry analysis to α-tubulin levels and reported in h1, and expressed as mean ± s.e.m. from n = 5/6 spinal cord for each group. *p < 0.05 vs Sham; ##p < 0.01 vs SCI.