Lauri Sari E, Lamsa Karri, Pavlov Ivan, Riekki Ruusu, Johnson Benjamin E, Molnar Elek, Rauvala Heikki, Taira Tomi
Department of Biosciences, Division of Animal Physiology, P.O. Box 65, University of Helsinki, 00014 Helsinki, Finland.
Mol Cell Neurosci. 2003 Jan;22(1):107-17. doi: 10.1016/s1044-7431(02)00012-x.
During development neuronal circuitries are refined by activity. Here we studied the role of spontaneous electrical activity in the regulation of synapse formation in the intact newborn (Postnatal Day 3; P3) rat hippocampus in vitro. The blockade of the spontaneous network activity with TTX led to an increase in the number of functional excitatory synapses in the CA3 area of the developing hippocampus. In parallel, there was a substantial increase in the expression levels of the presynaptic markers synaptophysin, synaptotagmin, and synapsin I and of GluR1 AMPA receptor subunits. These changes were associated with an increase in the frequency and amplitude of AMPA receptor-mediated miniature excitatory postsynaptic currents (mEPSCs). Our correlated immunocytochemical, electronmicroscopical, and electrophysiological experiments indicate that in the developing hippocampus spontaneous network activity controls the number of functional synapses.
在发育过程中，神经元回路通过活动得到完善。在此，我们研究了自发电活动在体外完整新生（出生后第3天；P3）大鼠海马体突触形成调控中的作用。用河豚毒素阻断自发网络活动导致发育中海马体CA3区功能性兴奋性突触数量增加。同时，突触前标志物突触素、突触结合蛋白和突触蛋白I以及GluR1 AMPA受体亚基的表达水平大幅增加。这些变化与AMPA受体介导的微小兴奋性突触后电流（mEPSCs）的频率和幅度增加有关。我们相关的免疫细胞化学、电子显微镜和电生理实验表明，在发育中的海马体中，自发网络活动控制着功能性突触的数量。
