胎鼠脊髓内源性NT-3及BDNF对脊髓神经元的营养作用

The neurotrophic effect of endogeneous NT-3 and BDNF of fetal mouse on the neurons of spinal cord

目的：研究发育中的胎鼠脊髓中神经营养因子－3（NT－3）和脑源性的神经营养因子（BDNF）的营养作用．方法：用抗NT－3及BDNF的抗体封闭小鼠胚胎脊髓内源性NT－3及BDNF，观察封闭后体外培养的脊髓神经元活性和突起生长的变化．结果：NT－3在小鼠脊髓神经元中广泛表达，其作用主要为促进脊髓神经元突起生长，不加抗体封闭式，突起平均长度为（362．062±166．381）μm，当封闭抗体浓度为5mm／L时，突起长度为（262．011±109．168）μm．BDNF免疫反应阳性细胞主要为大细胞和DRG神经元，其作用主要是促进神经元的存活，在封闭抗体浓度为6．25mg／L，4．34mg／L时吸光度（A）值显著低于对照组．结论：发育中胚胎小鼠脊髓中NT－3促进神经元突起生长，BDNF则促进神经元存活．

To study the neurotrophic effects of neurotrophic factor-3 (NT-3) and brain derived neuro-trophic factor(BDNF) in developing spinal cord of fetal mouse. Methods: The endogenous NT-3 and BDNF of fetal spinal cord were block with anti-NT-3 and anti-BDNF antibody. The veriation of survival and neurite growth of spinal cord neurons in vitro were observed. Results: Most neurions could express NT-3,but only DRG neurons and few large neurons were BDNF positive cells. NT-3 could enhance the neurite growth of neurons.The neurite length (362. 062±166. 381 ) in control group is significantly longer than the experiment group (262. 011±109. 168). BDNF could sustain the survival of neurons. When being added 6. 25 and 4. 34 mg/L anti-BDNF antibody into the wells, the absorbancy valve is significantly lower than that of control group. Conclusion: NT-3 could enhance the neurite growth and BDNF could sustain the survival of neurons in the developing spinal cord of mouse.