Abstract: Objective To investigate the cerebral ischemia/reperfusion protection mechanism of viper venom nerve growth factor(vNGF) by the change of expression of growth associated protein-43 (GAP-43) and neurological function.Methods 45 adult male Wistar rats (weight 220～280 g) were divided randomly into 3 groups: sham group(S, n=9), balanced salt solution group (BSS, n=9) and venom nerve growth factor group (vNGF, n=27). Each group was observed for 7 days. vNGF group was divided into 25 U, 50 U and 100 U subgroups respectively. The following indexes in 3 groups were observed respectively: neurologic deficits and the expression of GAP-43 (immunohistochemistry method).Results Neurological function: The scores of neurological function was 0 in S group. The neurological deficits score was lower at the same time in vNGF group than that in BSS group (P<0.05). Immunohistochemistry: GAP-43 expressed in both BSS group and vNGF group. The expression of GAP-43 in vNGF group increased in 25 U, and to maximum in 100 U. The expression of GAP-43 in BSS group was significantly lower than in vNGF group (P<0.05). Conclusion vNGF can effectively enhance and prolong the expression of GAP-43, increase the survival rats of nerve cells, and has the protection effect on nerve cells after cerebral ischemia injured.

Key words: rat, cerebal ischemia/reperfusion, viper venom nerve growth factor, growth associated protein-43