| 翻訳と辞書 |
| Synaptic fatigue ： ウィキペディア英語版 |
Synaptic fatigue
Synaptic fatigue, or short-term synaptic depression, is an activity-dependent form of short term synaptic plasticity that results in the temporary inability of neurons to fire and therefore transmit an input signal. It is thought to be a form of negative feedback in order to physiologically control particular forms of nervous system activity.〔Kilpatrick, Z. P. (2010). Spatially Structured Waves and Oscillations in Neuronal Networks With Synaptic Depression and Adaptation. Doctor of Philosophy, University of Utah.〕
It is caused by a temporary depletion of synaptic vesicles that house neurotransmitters in the synapse, generally produced by persistent high frequency neuronal stimulation. The neurotransmitters are released by the synapse to propagate the signal to the postsynaptic cell. It has also been hypothesized that synaptic fatigue could be a result of postsynaptic receptor desensitization or changes in postsynaptic passive conductance, but recent evidence has suggested that it is primarily a presynaptic phenomenon.〔Simons-Weidenmaier, N. S., Weber, M., Plappert, C. F., Pilz, P. K. D., & Schmid, S. (2006). Synaptic depression and short-term habituation are located in the sensory part of the mammalian startle pathway. BMC Neuroscience, 7, 38-38.〕〔Zhang, H., Gong, B., Liu, S., Fa, M., Ninan, I., Staniszewski, A., & Arancio, O. (2005). Synaptic fatigue is more pronounced in the APP/PS1 transgenic mouse model of Alzheimer's disease. Current Alzheimer Research, 2(2), 137-140.〕
==Background==
Chemical synapses allow for signal transmission by a presynaptic cell releasing neurotransmitters into the synapse to bind to receptors on a postsynaptic cell. These neurotransmitters are synthesized in the presynaptic cell and housed in vesicles until released. Once neurotransmitters are released into the synaptic cleft and a signal is relayed, re-uptake begins which is the process of transport proteins clearing out the neurotransmitters from the synapse and recycling them in order to allow for a new signal to be propagated. If stimulation is occurring at a high enough frequency and with enough strength, neurotransmitters will be released at a faster rate than re-uptake can recycle them which will ultimately deplete them until there are no longer readily releasable vesicles and a signal can no longer be transmitted.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
■ウィキペディアで「Synaptic fatigue」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|