期刊
NAUNYN-SCHMIEDEBERGS ARCHIVES OF PHARMACOLOGY
卷 387, 期 10, 页码 943-954出版社
SPRINGER
DOI: 10.1007/s00210-014-1005-1
关键词
Astrocytes; Neurons; Hippocampus; P2X7 receptors; Ca2+ imaging; Patch-clamp recording
资金
- Deutsche Forschungsgemeinschaft [IL 20/19-1]
- Mashad University of Medical Sciences, Mashad, Iran
P2X7 receptors have been suggested to be located both on neurons and astrocytes of the central and peripheral nervous systems. In the present Ca2+-imaging and patch-clamp study, we reinvestigated these findings on mixed neuronal-astrocytic cell cultures prepared from embryonic or newborn rat hippocampi. We found in a Mg2+-free bath medium that the prototypic P2X7 receptor agonist dibenzoyl-adenosine triphosphate (Bz-ATP) increased the intracellular Ca2+ concentration ([Ca2+](i)) both in the neuronal cell bodies and in their axo-dendritic processes only to a very minor extent. However, Bz-ATP produced marked [Ca2+](i) transients in the neuronal processes, when they grew above a glial carpet, which was uniformly sensitive to Bz-ATP. These glial signals might be misinterpreted as neuronal responses because of the poor focal discrimination by a fluorescent microscope. Most astrocytes had a polygonal shape without clearly circumscribable boundaries, but a subgroup of them had neuron-like appearance. The cellular processes of this astrocytic subgroup, just as their cell somata and their polygonal counterparts, appeared to possess a high density of functional P2X7 receptors. In contrast to astrocytes, in a low Ca2+/no Mg2+-containing bath medium, hippocampal neurons failed to respond to Bz-ATP with membrane currents. In addition, neither the amplitude nor the frequency of spontaneous excitatory postsynaptic currents, representing the quantal release of glutamate, was modified by Bz-ATP. We conclude that cultured hippocampal neurons, in contrast to astrocytes, possess P2X7 receptors, if at all, only at a low density.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据