The physiological function of (1) nerve growth factor can be summarized into three aspects: ① it has neurotrophic effect on the early development of nerve cells; ② Promoting the differentiation of nerve cells; ③ Influence on the tendency of neurite branching of nerve cells.

(2) The role of neurotrophic factor (NTFs): ① The dependent factors of survival and differentiation in neurogenesis are the regulatory factors of mature neurons, and also the necessary factors to protect their survival and promote their regeneration when neurons are damaged or diseased; ② The deletion or mutation of ②NTFs gene may be the cause of some neuronal diseases; ③ Neurotrophic factor has become a promising anti-neuronal degeneration factor.