Crépel Valérie, Aronov Dmitriy, Jorquera Isabel, Represa Alfonso, Ben-Ari Yehezkel, Cossart Rosa
INMED, INSERM, U29, Université de La Méditerranée, Parc scientifique de Luminy, BP 13, 13273 Marseille Cedex 09, France.
Neuron. 2007 Apr 5;54(1):105-20. doi: 10.1016/j.neuron.2007.03.007.
Correlated neuronal activity is instrumental in the formation of networks, but its emergence during maturation is poorly understood. We have used multibeam two-photon calcium microscopy combined with targeted electrophysiological recordings in order to determine the development of population coherence from embryonic to postnatal stages in the hippocampus. At embryonic stages (E16-E19), synchronized activity is absent, and neurons are intrinsically active and generate L-type channel-mediated calcium spikes. At birth, small cell assemblies coupled by gap junctions spontaneously generate synchronous nonsynaptic calcium plateaus associated to recurrent burst discharges. The emergence of coherent calcium plateaus at birth is controlled by oxytocin, a maternal hormone initiating labour, and progressively shut down a few days later by the synapse-driven giant depolarizing potentials (GDPs) that synchronize the entire network. Therefore, in the developing hippocampus, delivery is an important signal that triggers the first coherent activity pattern, which is silenced by the emergence of synaptic transmission.
相关神经元活动对神经网络的形成至关重要，但其在成熟过程中的出现情况却鲜为人知。我们使用多束双光子钙显微镜结合靶向电生理记录，以确定海马体从胚胎期到出生后阶段群体相干性的发展。在胚胎期（E16 - E19），不存在同步活动，神经元具有内在活性并产生L型通道介导的钙尖峰。出生时，通过缝隙连接耦合的小细胞集合自发产生与反复爆发放电相关的同步非突触钙平台。出生时相干钙平台的出现受催产素控制，催产素是一种引发分娩的母体激素，几天后逐渐被使整个网络同步的突触驱动的巨大去极化电位（GDPs）关闭。因此，在发育中的海马体中，分娩是触发第一个相干活动模式的重要信号，该模式会因突触传递的出现而沉默。
