Effects of antidepressant and treadmill gait training on recovery from spinal cord injury in rats

Study design: Experimental, controlled, animal study. Objectives: To evaluate the influences of antidepressant treatment, treadmill gait training and a combination of these therapies in rats with experimental, acute spinal cord injury (SCI). Setting: Brazil. Methods: 48 Wistar rats were given standardized SCI; rats were then randomly assigned to four treatment groups: (1) motor rehabilitation therapy for 1 hour daily (gait training); (2) daily treatment with the antidepressant, fluoxetine (0.3 ml per 100 g intraperitoneally), beginning 24 h after the trauma; (3) combined fluoxetine treatment and gait training, or (4) untreated (controls). Neurological recovery was tested with the Basso, Beattie and Bresnahan (BBB) scale at 2, 7, 14, 21, 28,35 and 42 days after injury. Moreover, on day 42, all rats underwent a motor-evoked potential test (MEP); then, after euthanasia, histopathological evaluation was conducted in the area of SCI. Results: Based on the BBB scale, the combined treatment group showed significantly greater improvement compared with the other three groups, from the 14th to the 42nd day of observation. The MEP revealed that all treated groups showed significant improvement compared with the control group (P<0.02 for latency and P<0.01 for amplitude). Conclusion: Our results indicated that a combination of antidepressant and treadmill gait training was superior to either treatment alone for improving functional deficits in rats with experimental, acute SCI.