1, neurotrophic factor refers to a protein factor produced by the body, which can promote the survival, growth and differentiation of nerve cells. It has always been thought that nerve growth factor mainly regulates the survival of neurons during development and has no effect on adult neurons.

2. Neurotrophic substances and the above-mentioned growth factors that can regulate the survival of nerve cells are collectively called neurotrophic factors. 2. Overview of neurotrophic factors 2 1 The structures of neurotrophic substances and their receptors such as NGF, BDNF, NT3, NT45 and NT6.

3. Nutritional factors These factors are also called neurotrophic factors. They are endogenous peptides, which can promote the growth and survival of neurons by preventing the influence of apoptosis receptors P75 and TGF-RI.

4. protein S 100 can be called neurotrophic factor in a sense, and its increase in injured glial cells is the expression of GFAP and S- 100 in the brain tissue around the focus of cerebral hemorrhage in rabbits at the molecular level.

5. These substances are called neurotrophic factors [9], including nerve growth factor, brain-derived neurotrophic factor BDNF, neurotrophin -3, neurotrophin -45(NT-45) and so on [10].