长期增强的突触特异性在短距离上会崩
1Max Planck Institute for Psychiatry, München-Martinsried, Germany.
Nature
|July 17, 1997
概括
长期增强 (LTP) 扩散到附近的突触,即使是那些在诱导过程中没有被激活的突触. 这一发现挑战了关于突触可塑性输入特异性的传统观点,而突触可塑性对于学习和记忆至关重要.
科学领域:
- 神经科学是一个神经科学.
- 突触性可塑性 突触性可塑性
- 细胞机制 细胞机制
背景情况:
- 长期增强 (LTP) 是学习和记忆的关键机制.
- 传统上,人们认为LTP仅在激活的突触处被诱导.
- 最近的研究表明,LTP可以扩散到邻近的神经元,但其扩散到输入纤维仍有争议.
研究的目的:
- 在更细的空间尺度上研究LTP的输入特异性.
- 确定LTP向非激活的突触传播的精确距离.
主要方法:
- 使用了一种新的局部超技术.
- 评估了高空间分辨率 (~30微米) 的LTP的突触特异性.
主要成果:
- 在70微米的感应部位内,LTP扩散到突触.
- 在附近的突触中发生了增强,无论它们的激活历史如何.
- 更远的突触没有显示强化,这表明传播有限.
结论:
- 突触可塑性,特别是LTP,在近距离情况下缺乏输入特异性.
- LTP的传播在空间上受到限制,影响附近的输入纤维.
- 这些发现完善了我们对突触修饰及其在神经回路中的作用的理解.
相关概念视频
Long-term Potentiation
Long-term potentiation, or LTP, is one of the ways by which synaptic plasticity—changes in the strength of chemical synapses—can occur in the brain. LTP is the process of synaptic strengthening that occurs over time between pre- and postsynaptic neuronal connections. The synaptic strengthening of LTP works in opposition to the synaptic weakening of long-term depression (LTD) and together are the main mechanisms that underlie learning and memory.
Long-term Depression
Long-term depression, or LTD, is one of the ways by which synaptic plasticity—changes in the strength of chemical synapses—can occur in the brain. LTD is the process of synaptic weakening that occurs over time between pre and postsynaptic neuronal connections. The synaptic weakening of LTD works in opposition to synaptic strengthening by long-term potentiation (LTP) and together are the main mechanisms that underlie learning and memory.
Long-term Potentiation
Long-term potentiation, or LTP, is one of the ways by which synaptic plasticity—changes in the strength of chemical synapses—can occur in the brain. LTP is the process of synaptic strengthening that occurs over time between pre and postsynaptic neuronal connections. The synaptic strengthening of LTP works in opposition to the synaptic weakening of long-term depression (LTD) and together are the main mechanisms that underlie learning and memory.
Hebbian LTP
LTP can occur when presynaptic neurons...
Hebbian LTP
LTP can occur when presynaptic neurons...
Long-term Depression
Long-term depression, or LTD, is one of the ways by which synaptic plasticity—changes in the strength of chemical synapses—can occur in the brain. LTD is the process of synaptic weakening that occurs over time between pre and postsynaptic neuronal connections. The synaptic weakening of LTD works in opposition to synaptic strengthening by long-term potentiation (LTP) and together are the main mechanisms that underlie learning and memory.
Calcium Ion Concentration Mechanism
If over time, all...
Calcium Ion Concentration Mechanism
If over time, all...
Chemical Synapses
Chemical synapses are specialized sites between two neurons or between a neuron and a non-neuronal cell like a muscle, glandular or sensory cell.
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Chemical Synapses
Chemical synapses are specialized sites between two neurons or between a neuron and a non-neuronal cell like a muscle, glandular or sensory cell.
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...


