Abstract: Objective To investigate the effect of local insulin injection on neurological function after crushed injury of facial nerve in rats. Methods Facial nerve was crushing injured in 30 Sprague-Dawley rats, from which 20 selected rats were divided into treatment group (n=10) and control group (n=10). The treatment group was injected with insulin 250 ng/kg at innervated muscle, and the control group was injected with normal saline. They were assessed with neurologic deficit score everyday within 7 days after injection, and the regeneration of nerve fiber was observed with retrograde fluorogold labeling. Results Compared with that in the control group, the neurological deficit score was improved more 5~7 days after injection in the treatment group, and the count of fluorogold labeling cells increased more in the treatment group. Conclusion Local injection of insulin can promote the recovery of neurological function after crushed injury of facial nerve.

Key words: facial nerve crushed injury, facial muscle, neurological function, nerve regeneration, insulin, rats