The Expression Of Nogo-A In Spinal Cord Segment Corresponding To Traumatic Sciatic Nerve

Objectives: To investigate the regularity of the expression of Nogo-A in spinal cord corresponding to traumatic sciatic nerve in the course of injury and repair.Methods: 150 healthy adult Sprague Dawley(SD)rats were randomly divided into 6 groups, 25 per group. Group 1: sciatic nerves were severed without repair; Group 2: sciatic nerves were cut followed by immediate anastomosis of nerval adventitia using 10/0 non-traumatic suture; Group 3: 1 cm of sciatic nerve was resected in every subjects; Group 4: 1 cm resection of sciatic nerve was replaced by the resected sciatic nerve in group 3; Group 5: 1 cm of sciatic nerve was severed followed by epineurial suture in situ; Group 6: Visualization of sciatic nerve was performed without injury to it. The rats of each group were randomly divided into 5 subgroups, 5 per subgroup. The five subgroups were sacrificed at different intervals, 1 day, 2 day, 1 week, 2 week, 32day after operation. The expression of Nogo-A in spinal cord were detected by immunohistochemical staining and quantified by mean optical density (MOD).Results: The expression of Nogo-A was positive in the cytochylema of motoneuron in anterior gray column of spinal cord. The MOD of traumatic side was evidently higher than non-traumatic side in group 1, 3, 5 at 1, 2 day after operation. The MOD of the severed side reached the top at 1 week.and then descented gradually, and almost normal at 32days after operation. The MOD of traumatic side was not statistically different from non-traumatic side in the group 2. The MOD of traumatic side raised remarkable at 1 ,2 day after operation in the group of altogeneic transplantation, descented a little at 1 week, reach top at 2 week and maintained high level afterwards.Conclusions: The expression of Nogo-A in motoneuron on traumatic side was higher than that on non-traumatic side. The expression of Nogo-A in traumatic side was different from non-traumatic side and came to normal on the condition that the traumatic nerve was immediately repaired by end-end anastomosis after injury. If the the traumatic nerve was replaced by allogeneic transplantation, the expression of Nogo-A in traumatic side were remarkable higher than that in non-traumatic side, and still maintained high level even after 1 month.