相关实验视频
Updated: Jun 25, 2026

06:32
Electrophysiological Recording From Drosophila Labellar Taste Sensilla
Published on: February 27, 2014
谷氨酸释放的敏感性在一个型终端中的谷氨酸
J H Bollmann1, B Sakmann, J G Borst
1Max-Planck-Institute for Medical Research, Department of Cell Physiology, Jahnstrasse 29, D-69120 Heidelberg, Germany. jbollman@mpimf-heidelberg.mpg.de
概括
这项研究揭示了大鼠听觉脑干突触中的高敏感性,其中细胞内的小增加迅速触发了谷氨酸的释放,影响了突触功能.
科学领域:
- 神经科学是一个神经科学.
- 突触生理学 突触生理学
- 听觉神经生物学 听觉神经生物学
背景情况:
- 突触疗效由突触前细胞内度 ([Ca2+]i) 调节.
- 了解在神经递质释放中的作用对于听觉处理至关重要.
研究的目的:
- 在大鼠听觉脑干突触中量化谷氨酸释放的敏感性.
- 为了比较引起的释放与生理动作潜能引起的释放.
主要方法:
- 化的激光光解用以精确控制预突触[Ca2+]i.
- 谷氨酸释放的反应被测量为受控的过渡物.
- 产生了释放的度-反应曲线.
主要成果:
- 一个[Ca2+]i增加到1微摩拉足以引起谷氨酸释放.
- 可释放囊泡池的快速耗尽发生在0.5毫秒内[Ca2+]i>30微米.
- 生理释放模式可以通过[Ca2+]i增加到大约10μmol复制.
结论:
- 听觉脑干突触对谷氨酸释放具有很高的敏感性.
- 阶段性和延迟释放机制之间的区别可能不如以前所认为的那么明显.
相关概念视频
Ligand-gated Ion Channels
Ligand-gated ion channels are transmembrane proteins with a channel for ions to pass through and a binding site for a ligand. The channel opens only when a ligand attaches to the binding site.
Three Subfamilies of Ligand-gated Ion Channels
Ligand-gated ion channels fall into three subfamilies. The 'Cys-loop' includes the nicotinic acetylcholine receptors, γ-aminobutyric acid (GABA), glycine, and 5-hydroxytryptamine receptors. The second one is the 'Pore-loop' channels that include the...
Three Subfamilies of Ligand-gated Ion Channels
Ligand-gated ion channels fall into three subfamilies. The 'Cys-loop' includes the nicotinic acetylcholine receptors, γ-aminobutyric acid (GABA), glycine, and 5-hydroxytryptamine receptors. The second one is the 'Pore-loop' channels that include the...
G-Protein Gated Ion Channels
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory organs,...
Sensory organs,...
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...
Local Anesthetics: Differential Sensitivity of Nerve Fibers
Local anesthetics (LAs) block the sodium channels of nerve trunks, sensory nerve endings, and neuromuscular junctions. Although LAs can block all kinds of nerves, the sensitivity of nerve fibers differs according to nerve types and structures. LAs are known to block myelinated fibers faster than unmyelinated ones. Also, they block pain or sensory neurons at low concentrations without affecting the motor neurons involved in muscle contractions. This helps relieve labor pain without affecting the...
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...
The Physiology of Taste
The perception of a salty flavor is facilitated by sodium ions within the oral salivary fluid. Upon consumption of a salty substance, salt crystals disassemble, leading to the liberation of its constituents—Na+ and Cl- ions. These ions subsequently dissolve into the salivary fluid present in the oral cavity. The external environment of the gustatory cells experiences an elevation in Na+ concentration, thereby establishing a potent concentration gradient. This gradient propels the diffusion of...

