Nerve regeneration factor promotes nerve regeneration after sciatic nerve injury in rats
- Author:
Ming-Ming ZHOU
1
Author Information
1. The Key Laboratory of Neuroregeneration of Jiangsu Province
- Publication Type:Journal Article
- From:
Academic Journal of Second Military Medical University
2006;27(9):937-940
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To investigate the promoting effect of nerve regeneration factor (NRF) on nerve regeneration after sciatic nerve injury in rats. Methods: Thirty Sprague-Dawely rats, including 15 females and 15 males, were equally randomized into 3 groups: low dose NRF group, high dose NRF group and control group. Rats' sciatic nerves were injured by crushing and sciatic function index (SFI) was determined by walking tract analysis at days 10, 15 and 20 after crushing. Then sciatic nerves on both sides were dissociated for electrophysiology study and the recovery rate of nerve conduction velocity (NCV) was calculated. Then, 2 rats were randomly selected from each group and the ultrastructure of regenerated sciatic nerves was observed by electron microscope. Meanwhile, the spinal cord segments (L4-L6), the distal site of injured sciatic nerve and the injured gastrocnemius muscle in other rats were observed by light microscope. The count of motor neurons of anterior horn, the number of myelinated fibers, the transverse section area of gastrocnemius muscle cells and other parameters were determined. Results: At day 10 after crushing, SFI scores had no significant difference between 3 groups; at day 15 after crushing, SFI score of high dose NRF group was significantly higher than that of the control group (P<0.01); at day 20 after crushing, SFI scores of 2 NRF groups were significantly higher than those of the control group (P<0.01, P<0.05). At day 20 after crushing, the recovery rates of NCV in the high dose group, the low dose group and the control group were (57±26)%, (44±15)% and (31±9)%, respectively, with significant difference between the high dose group and the control group (P<0.05). Compared with the control group, the high dose group had more mature myelinated nerve fibers and less degenerated nerve fibers. In the high dose group, the layout of regenerated nerve fibers was dense and well-arranged, the gastrocnemius muscle cells was well alive and neatly arranged, and the bilateral motor neurons of anterior horn was more close to each other. The numbers of motor neurons of anterior horn and myelinated nerve fibers in high dose group were significantly higher than those in control group (P<0.05,P<0.01); the transverse section areas of gastrocnemius muscle cells in both NRF groups were significantly higher than those in the control group (P<0.01,P<0.05). Conclusion: NRF can promote the regeneration of peripheral nerves and improve the recovery of their function.
