Effects of exercise and fetal spinal cord implants on the H-reflex in chronically spinalized adult rats.

This study investigated the modulation of hindlimb reflex excitability after transection of the spinal cord in adult rats. After transection, the H-reflex exhibited decreased depression at high stimulation frequencies compared to intact animals. Groups of animals which received a spinal cord transection followed by either an exercise regimen for the hindlimbs or a fetal spinal cord implant, showed high stimulation frequency depression similar to controls. This suggests that each of these palliative strategies helped to "normalize' the excitability of specific spinal reflexes.