Department of Neuroscience and Pharmacology, Copenhagen University, Panum Institute, 12.3, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark.
Neurosci Lett. 2013 Oct 11;553:78-83. doi: 10.1016/j.neulet.2013.08.022. Epub 2013 Aug 21.
Multiple regions in the CNS display propagating correlated activity during embryonic and postnatal development. This activity can be recorded as waves of increased calcium concentrations in spiking neurons or glia cells, and have been suggested to be involved in patterning, axonal guidance and establishment of synaptic transmission. Here, we used calcium imaging in slice cultures of the postnatal cerebellum, and observe spontaneous propagating calcium waves in NeuN-positive granule-like cells. Wave formation was blocked by TTX and the AMPA antagonist NBQX, but persisted after NMDA receptor blockade with MK-801. Whole-cell recordings during wave formation showed cyclic EPSP barrages with an amplitude of 10-20 mV concurrent with wave activity. Local non-propagating putative transglial waves were also present in the cultures, and could be reproduced by pressure application of ATP. We hypothesize, that the propagating wave activity is carried through the tissue by axonal collaterals formed by neighboring granule cells, and further suggest that the correlated activity may be related to processes that ensure correct postnatal wiring of the cerebellar circuits.
中枢神经系统的多个区域在胚胎和出生后发育过程中显示出传播相关的活动。这种活动可以被记录为神经元或神经胶质细胞中钙浓度增加的波，并且被认为参与了模式形成、轴突导向和突触传递的建立。在这里，我们使用出生后小脑的切片培养物中的钙成像，观察到 NeuN 阳性颗粒样细胞中的自发传播钙波。波的形成被 TTX 和 AMPA 拮抗剂 NBQX 阻断，但在用 MK-801 阻断 NMDA 受体后仍然存在。波形成过程中的全细胞记录显示，与波活动同时出现的是幅度为 10-20 mV 的周期性 EPSP 爆发。培养物中也存在局部非传播的假定跨胶质波，并且可以通过 ATP 的压力施加来再现。我们假设，传播的波活动是由相邻颗粒细胞形成的轴突侧支在组织中传递的，并且进一步表明，相关的活动可能与确保小脑回路在出生后正确布线的过程有关。
