相关实验视频
Updated: May 2, 2026
11:02
Presynaptically Silent Synapses Studied with Light Microscopy
Published on: January 5, 2010
10.9K
多种形式的突触可塑性是由选择性抑制单个神经元活动引发的
Juan Burrone1, Michael O'Byrne, Venkatesh N Murthy
1Department of Molecular & Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Nature
|December 3, 2002
概括
中枢神经系统中神经元活动的选择性抑制可以触发恒常性突触可塑性. 这与全球活动抑制形成鲜明对比,揭示了突触修饰的独特机制.
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
- 中枢神经系统的调节规则
背景情况:
- 在中枢神经系统 (CNS) 中长期突触修饰的机制仍然不完全理解.
- 虽然竞争规则诱导了局部突触变化,但恒常性可塑性促进了神经元范围内的稳定性调整.
- 以前的研究经常在全球范围内操纵神经元活动,限制了对选择性影响的洞察力.
研究的目的:
- 调查选择性抑制 hippocampal 个体神经元中的刺激性对突触输入的影响.
- 为了区分早期 (前synaptogenesis) 和晚期 (后synaptogenesis) 活动操纵的影响.
- 探索对有针对性的神经元活动减少的恒常反应.
主要方法:
- 在一个活跃网络中的单个海马神经元中过度表达一个向内调整器通道.
- 在不同发育阶段 (突触形成前后) 操纵神经元刺激能力.
- 功能性突触输入和神经元活动水平的评估.
主要成果:
- 在突触形成之前减少单个神经元的活动导致功能突触输入减少.
- 在所有神经元中均地抑制活动并没有导致类似的减少.
- 在已建立的突触中选择性抑制活动诱导了突触输入的恒常性增加,恢复神经元活动.
结论:
- 选择性和全球性活动抑制会引起明显的突触修饰.
- 活动操纵的时间 (早期与晚期) 显著影响突触输入调节.
- 恒常性可塑性机制可以弥补神经元活动的选择性减少,以保持网络稳定性.
相关概念视频
01:35Long-term Potentiation
51.6K
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.
51.6K
01:05Long-term Depression
27.3K
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.
27.3K
01:29Excitatory and Inhibitory Effects of Neurotransmitters
12.1K
When an action potential reaches the presynaptic axon terminal, it releases neurotransmitters from the neuron into the synaptic cleft at a chemical synapse. The released neurotransmitter can be excitatory or inhibitory. The critical criteria commonly used to determine whether a molecule is a neurotransmitter at a chemical synapse are the molecule's presence in the presynaptic neuron. Second, its release is in response to strong presynaptic depolarization. And lastly, the presence of...
12.1K
01:25Long-term Potentiation
2.7K
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...
Hebbian LTP
LTP can occur when...
2.7K
01:03Long-term Depression
2.6K
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...
Calcium Ion Concentration Mechanism
If over...
2.6K
01:28Integration of Synaptic Events
6.4K
Synaptic integration mainly includes the summation of graded potentials. Graded potentials, regardless of their type, cause subtle alterations in membrane voltage, resulting in either depolarization or hyperpolarization. These incremental changes, when combined or summed, can propel the neuron toward its threshold. Consider, for example, a membrane experiencing a +15 mV shift, causing it to depolarize from -70 mV to -55 mV. In this scenario, graded potentials govern the membrane's ability to...
6.4K