Brain-derived neurotrophic factor and peripheral nerve regeneration: a functional evaluation.

The potential benefit of brain-derived neurotrophic factor (BDNF) on motor-nerve regeneration after transection injury in 24 adult rats was evaluated after entubulation repair. Gait analysis for ankle angle and tension transduction device (TTD) strain-gauge measurements yielded functional evaluation of regeneration. The BDNF (15 mg/mL) or phosphate buffered saline (control) was injected into the silicone elastomer (Silastic) channel. Gait analysis performed 0, 2, 4, 6, 10, and 12 weeks after injury demonstrated a significant difference between uninjured and injured legs of 23 and 43 degrees, respectively (P<.001, analysis of variance). The TTD evaluation 13 weeks after injury demonstrated a significant decrease in force development of injured compared to uninjured legs, 148 and 58 g, respectively (P<.001). No functional benefits were demonstrated between BDNF-treated versus control-treated animals in either model for a single exposure to BDNF.