[Effect of chondroitinase ABC on growth associate protein 43 and glial fibrillary acidic protein after spinal cord injury in rats].

Objective: To investigate the effect of chondroitinase ABC (ChABC) on the expression of growth associated protein 43 (GAP-43) and glial fibrillary acidic protein (GFAP) after spinal cord injury (SCI) in rats.

Methods: A total of 150 adult female SD rats, weighing 250-300 g, were randomly divided into ChABC treatment group (group A), saline treatment group (group B), and sham operation group (group C) with 50 rats in each group. In groups A and B, the rats were made the SCI models and were treated by subarachnoid injection of ChABC and saline; in group C, the rats were not treated as a control. At 1, 3, 7, 14, and 21 days after operation, the Basso, Beattie, and Bresnahan (BBB) score system was used to evaluate the motion function, and immunofluorescent histochemical staining was used to observe the expressions of GAP-43 and GFAP.

Results: At different time points, the BBB scores of groups A and B were significantly lower than those of group C (P < 0.05); there was no significant difference in BBB score between groups A and B after 1, 3, and 7 days of operation (P > 0.05), but the BBB score of group A was significantly higher than that of group B after 14 and 21 days of operation (P < 0.01). At different time points, the GAP-43 and GFAP positive neurons of groups A and B were significantly higher than those of group C (P < 0.05). After 14 and 21 days of operation, the GAP-43 positive neurons of group A were more than those of group B (P < 0.01). After 7, 14, and 21 days of operation, the GFAP positive neurons of group A were significantly less than those of group B (P < 0.01).

Conclusion: ChABC can degrade glial scar, improve the microenvironment of the injured region and enhance the expression of GAP-43, which promotes axonal growth and extension.