Nerve growth factor modulates bone morphogenetic protein expression in rabbit fracture

Abstract

To explore the regulation of the expression of bone morphogenetic protein (BMP) of nerve growth factor (NGF) and examine the mechanism of nerve growth factor in promoting fracture repair. A total of 108 healthy New Zealand white rabbits, weighting 2.5-3.0 kg, male or female, were randomly divided into 3 groups of NGF (Group A), antagonistic NGF (Group B) and control (Group C) (n = 36 each). A standard model of right mid-piece radial fracture was established. Group A received an intravenous injection of NGF 200 ng/kg twice daily 1 week while group B an intraperitoneal injection of NGF antibody 400 ng thrice daily for 3 weeks; group C physiological saline 1 ml twice daily for 3 weeks. And 6 rabbits in each group were sacrificed at 24 h, 48 h, 1 week, 3 weeks, 6 weeks and 8 weeks respectively. And BMP proteins of fracture specimens were analyzed by Western immunoblot. NGF promoted the expression of BMP in fracture while NGF antagonist inhibited its expression. NGF group produced more BMP earlier than control or NGF antagonist group during fracture healing while the production of BMP was more pronounced in control group than that in NGF antagonist group during fracture healing. And the differences were statistically significant (P < 0.05). Capable of promoting the expression of BMP in radial fracture of rabbit, NGF may be beneficial to fracture healing directly or indirectly.