ACTIVITY-DEPENDENT REGULATION OF NEURAL CELL ADHESION MOLECULES, NEUROTROPHINS AND THEIR RECEPTORS IN NEURONS.

研究了小鼠背根神经节(DRG)神经元在体外发育过程中神经元活性、神经细胞黏附分子和神经营养因子之间的关系。神经系统结构是通过神经回路的电活动来改变的，但其分子机制还不是很清楚。识别分子和神经营养因子调节发育过程中的细胞相互作用。因此，通过向培养的小鼠背根神经节神经元传递电脉冲，研究了神经细胞黏附分子(L1、NCAM和N-钙粘素)和神经营养因子(NGF、BDNF和NT-3)在活动发育中的可能参与。NGF作用5天后，NT-3和L1水平升高3~4倍，而BDNF作用不明显。在没有NGF的情况下，低频刺激(0.1赫兹，持续5天)可降低L1和trkC水平。通过特定的脉冲活动模式调节L1和trkC的表达，可能会影响细胞之间的相互作用，协调神经系统在关键发育阶段的结构和功能。

We studied the relationship between neuronal activity, neural cell adhesion molecules and neurotrophins in mouse dorsal root ganglion (DRG) neurons during development in vitro. The nervous system structure is modified by electrical activity in developing neural circuits, but the molecular mechanisms are not well under stood. Recognition molecules and neurotrophic factors regulate cell interactions during development. Therefore, the possible involvement of neural cell adhesion molecules (L1, NCAM and N-cadherin), and of neurotrophins (NGF, BDNF and NT-3) in activity-development was studied by delivering electrical pulses to mouse DRG neurons in cultures. After 5 days exposure to NGF, but not after exposure to BDNF, the NT-3 and L1 levels increased 3〜4 fold. Low frequency stimulation (0.1 Hz for 5 days) decreased L1 and trkC levels in the absence of NGF. Regulation of the expression of L1 and trkC by specific patterns of impulse activity may influence cell interactions coordinating structure and function of the nervous system at critical developmental stages.