Sprouting of brainstem-spinal tracts in response to unilateral motor cortex stroke in mice.

After a stroke to the motor cortex, sprouting of spared contralateral corticospinal fibers into the affected hemicord is one mechanism thought to mediate functional recovery. Little is known, however, about the role of the phylogenetically old, functionally very important brainstem-spinal systems. Adult mice were subjected to a unilateral photothrombotic stroke of the right motor cortex ablating 90% of the cross-projecting corticospinal cells.

Deep brain stimulation of the midbrain locomotor region improves paretic hindlimb function after spinal cord injury in rats.

In severe spinal cord injuries, the tracts conveying motor commands to the spinal cord are disrupted, resulting in paralysis, but many patients still have small numbers of spared fibers. We have found that excitatory deep brain stimulation (DBS) of the mesencephalic locomotor region (MLR), an important control center for locomotion in the brain, markedly improved hindlimb function in rats with chronic, severe, but incomplete spinal cord injury. The medial medullary reticular formation was essential for this effect.