Motor cortex after C3 lesion

Gene expression analysis of motor cortex after spinal C3 lesion Dorsal column wire knife lesions: Adult female Fischer 344 rats weighing 150-200 gm were used. Animals underwent a laminectomy at spinal level C3. Dorsal funiculus lesions were made in the middle of C3 using a Kopf microwire device (Kopf Instruments, Tujunga, CA). After fixation in a spinal stereotaxic unit, a small dural incision was made. The wire knife was lowered into the spinal cord to a depth of 1.1 mm ventral to the dorsal cord surface and 1.1 mm to the left of the midline. The tip of the wireknife was extruded, forming a 2.25 mm-wide arc that was raised to the dorsal surface of the cord. To ensure complete axotomy of the dorsal funiculus, spinal tissue was compressed against the microwire knife surface using a microaspiration pipette until all visible white matter was transected. Cortical microdissection: The forelimb and hindlimb motor cortex were microdisected from rat cortices: Rostral to Bregma: an area from 2.0 to 4.5 mm mediolateral and from 0 to 2 mm anterior-posterior Caudal to Bregma: an area from 2.0 to 3.5 mediolateral and from 0 to 3 mm caudal to Bregma. Only the inferior half of the cortex containing layer V corticospinal motor neurons was sampled in each region.