Hebbianは,神経筋シナプスの単離を in vitro で抑える
Science (New York, N.Y.)
|June 12, 1992
まとめ
シナプスの可塑性,またはヘッビアン調節は,周辺シナプスで観察されました. ポストシナプス活動だけではシナプス抑うつを引き起こし,カルシウムの流入を必要とし,逆行シグナル伝達を示唆しました.
科学分野:
- 神経科学は神経科学である.
- シナプス性可塑性 (Synaptic Plasticity) とは,シナプス性可塑性 (Synaptic Plasticity) とは,シナプス性可塑性 (Synaptic Plasticity) とは,シナプス性可塑性 (Synaptic Plasticity) とは,シナプス性可塑性 (Synaptic Plasticity) とは,シナプス性可塑性 (Synaptic Plasticity) とは,シナプス性 (Synaptic Plasticity) とは,シナプス性 (Synaptic Plasticity) とは,シナプス性 (Synaptic Plasticity) とは,シナプス性 (Synaptic Plasticity) とは,シナプス性 (Synaptic Plasticity) とは,シナプス性 (Synaptic Plasticity) とは
- 細胞および分子生物学
背景:
- シナプス効果の調節は,神経機能にとって極めて重要です.
- シナプス調節におけるシナプス前とシナプス後の活動間の時間的な相関の役割は,特に周辺シナプスでは完全に理解されていません.
研究 の 目的:
- 孤立した神経筋シナプスにおけるシナプスの有効性に対するシナプス前およびポストシナプス活動の間の時間的な相関の影響を調査する.
- 活動に依存したシナプス調節の根本的なメカニズムを決定する.
主な方法:
- 培養された孤立した神経筋肉のシナプスで実験が行われました.
- アセチルコリンのパルスは,非同期的なプレシナプス活性と,非同期的なプレシナプス活性なしに,ポストシナプス的に適用されました.
- 同期的なシナプス前およびシナプス後共同活性化もテストされました.
- 誘発されたトランスミッター放出とポストシナプス細胞性カルシウム濃度が測定されました.
主要な成果:
- 単体または非同期的なプレシナプス活性による反復的なポストシナプスアセチルコリン投与は,即座かつ持続的なシナプス低下を誘発した.
- 同期的なシナプス前およびシナプス後共同活性化はシナプス抑うつを引き起こさなかった.
- シナプス性うつ病は,誘発されたトランスミッター放出の減少に起因した.
- シナプスうつ病の誘導は,シナプス後の細胞塩酸カルシウム濃度の上昇を必要とした.
結論:
- ハッビアン調節は,シナプス可塑性の1つの形態であり,in vitroでは,孤立した周辺シナプスで作用する.
- トランスシナプス逆行相互作用は,このシナプス低下の基礎となる重要なメカニズムとして関与しています.
- ポストシナプスカルシウム流入は,これらのシナプスにおけるヘッビアン変調の誘導に不可欠です.
関連する概念動画
01:05Long-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.
01:29Excitatory and Inhibitory Effects of Neurotransmitters
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 specific...
01:03Long-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...
01:26Chemical 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...
01:29Neuromuscular Junction And Blockade
The site of chemical communication between a motor neuron and a muscle fiber is called the neuromuscular junction (NMJ). The end of the motor neuron at the NMJ divides into a cluster of synaptic end bulbs. The cytoplasm of these bulbs consists of synaptic vesicles enclosing acetylcholine molecules, the principal neurotransmitter released at the NMJ. The region opposite the synaptic bulb that ends in the muscle fiber is called the motor end plate, which has acetylcholine receptors. Within the...
01:26Chemical 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...