Simple technique help rats train and regain assisted walking

There has been a lot of publicity recently on the restoration of over-ground walking in completely transected rats using a cocktail of interventions that include epidural electrical stimulation, drug combinations delivered to the motor circuitry and robotic assistance and treadmill training. An example can be seen here.

While these studies were impressive, they did suggested that rats differed from cats, for example, which can express coordinated walking patterns after a few weeks of treadmill training without the need for all that epidural stimulation and drug cocktail. Are mammals really that different in their locomotor circuitry? A poster by O Alluin [Presentation #378.15] argued against this. The group from Montreal, Canada took completely spinalised rats (complete cord transection at T8) and trained them on a treadmill for 11 weeks for 10 mins per day whilst mechanically stimulating the perineal area with a pinch. The mechanical and sensory information flows to the cord and stimulating the lumbar region containing the central pattern generators for locomotion. It was interesting to see the data and video evidence that this simple technique brought about robust recovery of alternating, coordinated hind limb motion. Alluin explained the intensity of the pinch needs to be quite strong at the beginning of training but that this could be reduced significantly as time went on. One obvious extension of this will be to test whether external electrical stimulation in the perineal region also elicits a response. I got the impression they had tried this but weren’t prepared to comment at this stage.