不同类型的通道调解了中央突触传输
1Department of Physiology, Kyoto University Faculty of Medicine, Japan.
Nature
|November 11, 1993
概括
取决于电压的通道介导突触传输. P型和N型通道参与中枢神经系统神经递质的释放,而P型通道起着更重要的作用.
科学领域:
- 神经科学是一个神经科学.
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 突触传输依赖于前突触终端的电压依赖通道的流.
- 负责中枢突触中神经递质释放的通道的特定亚型仍然在很大程度上没有被描述.
研究的目的:
- 为了确定介导哺乳动物中枢神经系统中突触传播的通道的特定亚型.
- 研究N型和P型通道在刺激和抑制后突触电流中的作用.
主要方法:
- 使用特定类型的通道阻塞剂,包括欧米茄-毒素GVIA (N型) 和欧米茄-Aga-IVA (P型),用于后突触电流.
- 在老鼠小脑,脊髓和海马体的薄片中记录了后突触电流.
- 评估了L型通道阻断剂尼卡迪平的作用.
主要成果:
- 欧米茄-Aga-IVA显著抑制了小脑和脊髓神经元中的抑制后突触电流,以及海马神经元中的刺激后突触电流.
- 欧米茄毒素GVIA部分抑制了这些后突触电流.
- 尼卡迪平对突触传输没有显著影响.
结论:
- 至少有两种类型的通道,主要是P型和N型,在哺乳动物中枢神经系统中介于突触传输.
- 与N型道相比,P型道在调解突触传输方面似乎发挥了更为主导的作用.
相关概念视频
The Synapse
Neurons communicate with one another by passing on their electrical signals to other neurons. A synapse is the location where two neurons meet to exchange signals. At the synapse, the neuron that sends the signal is called the presynaptic cell, while the neuron that receives the message is called the postsynaptic cell. Note that most neurons can be both presynaptic and postsynaptic, as they both transmit and receive information.
Electrical Synapses
Electrical synapses found in all nervous systems play important and unique roles. In these synapses, the presynaptic and postsynaptic membranes are very close together (3.5 nm) and are actually physically connected by channel proteins forming gap junctions.
Gap junctions allow the current to pass directly from one cell to the next. In contrast, in the chemical synapse, the neurotransmitters carry the information through the synaptic cleft from one neuron to the next. They consist of two...
Gap junctions allow the current to pass directly from one cell to the next. In contrast, in the chemical synapse, the neurotransmitters carry the information through the synaptic cleft from one neuron to the next. They consist of two...
The Role of Ion Channels in Neuronal Computation
A postsynaptic neuron usually receives numerous impulses from several other presynaptic neurons. The axon hillock of the postsynaptic neuron integrates all these signals and determines the likelihood of firing an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential.
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...
Ligand-Gated Ion Channel Receptor: Gating Mechanism
Ligand-gated ion channels are transmembrane proteins that play a vital role in intercellular communication and functions of the nervous system. They allow the influx of ions across the membrane once the neurotransmitter binds, allowing the subsequent transmission of electrical excitation across the neurons. Other ligand-gated ion channels, like the γ-aminobutyric acid (GABA) receptor, permit anions like chloride into the cells on the binding of the GABA molecule. Their entry into the cell...
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...


