Ockel M, Lewin G R, Barde Y A
Department of Neurobiochemistry, Max-Planck Institute for Psychiatry, Planegg-Martinsried, Germany.
Development. 1996 Jan;122(1):301-7. doi: 10.1242/dev.122.1.301.
The neurotrophins nerve growth factor, brain-derived neurotrophic factor and neurotrophin-3 are structurally related proteins regulating the number of neurons in peripheral ganglia of the nervous system. Increased levels of nerve growth factor or of brain-derived neurotrophic factor selectively prevent normally occurring neuronal death, while the targeted elimination of all three genes decreases neuronal numbers. As previous studies indicated that the lack of neurotrophin-3 affects sensory ganglia already during gangliogenesis, the levels of this neurotrophin were increased during selected periods of chick development. We found that early, but not late, applications of neurotrophin-3 lead to a marked decrease in neuronal numbers in peripheral sensory ganglia. This decrease is not seen with BDNF and does not selectively affect subtypes of dorsal root ganglion neurons. It is accompanied by, and might result from, a decrease in the number of proliferating neuroblasts in sensory ganglia of treated embryos.
神经营养因子神经生长因子、脑源性神经营养因子和神经营养因子-3是结构相关的蛋白质，它们调节神经系统外周神经节中的神经元数量。神经生长因子或脑源性神经营养因子水平的升高选择性地阻止正常发生的神经元死亡，而靶向消除所有这三个基因会减少神经元数量。由于先前的研究表明，神经营养因子-3的缺乏在神经节形成过程中就已经影响感觉神经节，因此在鸡发育的特定时期提高了这种神经营养因子的水平。我们发现，早期而非晚期应用神经营养因子-3会导致外周感觉神经节中的神经元数量显著减少。脑源性神经营养因子不会出现这种减少，并且不会选择性地影响背根神经节神经元的亚型。它伴随着处理过的胚胎感觉神经节中增殖神经母细胞数量的减少，并且可能是由这种减少导致的。
