期刊
NEUROSCIENCE RESEARCH
卷 43, 期 2, 页码 135-146出版社
ELSEVIER IRELAND LTD
DOI: 10.1016/S0168-0102(02)00028-7
关键词
shaft synapse; perforated synapse; synaptic spinule; long-term potentiation; remodeling; nicotinic
Synaptic plasticity associated with long-term potentiation was studied electrophysiologically and ultrastructurally in the cat superior cervical ganglion in situ. The preganglionic nerve fiber was stimulated at 10 Hz for 50 s for conditioning and then at I Hz for 1-3 h to monitor changes in the postganglionic compound action potential (PGP). The present material has shown the long-term potentiation (LTP), around 120% of the control, which lasted for up to 3 h. Fifteen of 18 ganglia (83%) have shown LTP. Ultrastructural studies demonstrated the synaptic structural remodeling: (1) The preganglionic nerve terminals ordinarily made mainly asymmetrical type of shaft synapses directly with dendrites of the ganglion cells that lacked dendritic spines; (2) conditioning tetanus rapidly remodeled simple shaft synapses into perforated ones characterized by perforations in the postsynaptic density (PSD), some of which had synaptic spinules associated with the perforated PSDs, i.e. spinule-synapses; (3) a rapid increase in the number of both structures was detected immediately after the tetanus. Perforated synapses and the spinule-synapses increased from 5% and 0% in the control to 27 and 9% at 0 min, respectively. Spinule-synapses occurred about one-third of the perforated shaft synapses; (4) Increased numbers of restructured shaft synapses was maintained for 15 min in ganglia expressing LTP; (5) Remodeled synapses did not increase in ganglia that did not express LTP or ganglia that were activated at 0.5 or I Hz. It was suggested a rapid increase in the number of remodeled synapses associated with the onset of LTP and its durability at its earlier phases in the cat SCG. (C) 2002 Elsevier Science Ireland Ltd and the Japan Neuroscience Society. All rights reserved.
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