These rats are back in action!
Grégoire Courtine and his team at The École polytechnique fédérale de Lausanne (EPFL) have been using a robotic harness and electro-chemical stimulation to get rats with damaged spinal cords up and running again.
The special harness frees the rodents from the pull of gravity without doing any of the work of locomotion for them. But before the rat is harnessed, something is required to wake the spinal cord out of its state of dormancy; a cocktail is just the pick me up the little critter needs— an injection of a special mixture of chemicals that replace neurotransmitters normally released by brainstem pathways. The chemicals prepare the rat’s neurons for lower body movement by exciting them and to complete the ¨wake-up¨ process, the outer layer of the rat’s spinal cord is stimulated with continuous electrical signals to further excite the neurons controlling leg movement.
In previous studies, scientists had already been successful in restoring leg movement to paralyzed rodents by stimulating their damaged spinal cords however, those trials were carried out with treadmills which prompted forward motion of the rats. Now that the team has switched to the use of the robotic harness, researchers can show that that the rats are actually able to move forward on their own. Furthermore, ¨willpower-based training translated into a fourfold increase in nerve fibers throughout the brain and spine— a regrowth that proves the tremendous potential for neuroplasticity even after severe central nervous system injury,” states Janine Heutschi, co-author of the study, in the EPFL press release.
Researchers are very optimistic about their findings, hoping the breakthrough will soon be able to provide more treatment options for people with spinal cord injury. The study is planned to progress into clinical trials within the next two years at the at Balgrist University Hospital Spinal Cord Injury Centre in Zurich, Switzerland.
This study was published in Science on June 1, 2012. You can access the full paper HERE