Introduction: The usefulness of whole-body vibration (WBV) as a therapeutical method after spinal cord injury (SCI), has received little attention in animal SCI-models and clinical settings.
Materials and Methods: We performed severe compressive SCI at a low-thoracic level in Wistar rats followed by daily WBV starting 1, 7, 14 or 28 days after injury (WBV1, WBV7, WBV14, WBV28) and continued for 12 weeks after the injury. As controls served rats euthanized in the first 2 weeks post SCI (subacute), with no WBV training (Sham), treated with passive flexion-extension (PFE) and intact animals. The changes in the average optical density (OD/µm2) of white matter in luxol fast blue stained longitudinal sections through the spinal cord were measured. Three types of regions of interest (RoIs) were considered: area with visible damage; a region, adjacent to the damage (penumbra); and distant visibly undamaged area. In an attempt to improve the previously used method for quantification we added a fourth RoI type- tissue bridges in the periphery of the damaged area- as one of the possible morphological substrates for the restoration of connectivity.
Results: The average OD in the visibly damaged areas was low in all animals as compared to intact ones, and there were no differences amongst the treatment groups. The penumbra and the distant visibly undamaged area showed different degree of remyelinaton in the different groups.
Conclusion: The analysis of the ODs suggests that WBV7 and WBV14 enhance remyelination in the penumbra of the injury as well as in distant seemingly intact tissues. Results were compared to our previous measurements that didn`t discriminate between grey and white matter.
