ノルエピネフリン誘発の細胞内Ca2+増加は,アストロサイトBKチャネル活性化と毛細血管応答と結びついています
Jelena Bogdanović Pristov1, Danijela Bataveljić2,3, Dunja Bijelić2
1Department of Life Sciences, Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Republic of Serbia.
American journal of physiology. Cell physiology
|August 25, 2025
まとめ
ノルエピネフリンはアストロサイトにおけるカルシウム増加を引き起こし,アルファ1- アドレナゲン受容体とBKチャネルを活性化させます. この信号伝達経路は 皮質の毛細血管の直径を縮小し 脳の血流に影響します
科学分野:
- 神経科学
- 細胞生物学
- 生理学
背景:
- ニューロンと血管と相互作用します ニューロンと血管と相互作用します
- 細胞内カルシウム (Ca2+) を介して神経活動と血管の直径を調節する.
- ノルエピネフリンはアストロサイト機能に影響するが,Ca2+シグナル伝達に対する正確な下流効果は不明である.
研究 の 目的:
- ノルエピネフリンによるCa2+増加とアストロサイト活動との因果関係を調査する.
- この過程におけるアルファ1-アドレナゲン受容体とBKチャネルの役割を決定する.
- 毛細血管直径の調節に対するアストロサイト-BKチャネル結合の貢献を明らかにする.
主な方法:
- ネズミの皮質からの原始アストロサイト培養
- アルファ1- アドレナゲン受容体,細胞内Ca2+貯蔵体,BKチャネルの薬理学的操作.
- Ca2+イメージングと電気生理学
- 毛細血管の直径の変化を評価するための急性脳切片の準備
主要な成果:
- ノルエピネフリンによって誘発された Ca2+ の増加は,アルファ1- アドレナジック受容体と BK 経路の活性化と因果的に関連しています.
- BKチャネルの活性化は,細胞内Ca2+貯蔵とアルファ1- アドレナゲン受容体のシグナル伝達に依存しています.
- アストロサイト Ca2+-BKチャネル結合は皮質毛細血管の直径を減少させる.
- この効果は,アストロサイトサイレンシングまたはBKチャネルブロックによって阻害され,直接のBKチャネル活性化によって模倣されます.
結論:
- Ca2+とBKチャネルを含むノレピネフリンに対する新種の細胞反応が特定される.
- この経路は皮質毛細血管の直径を直接調整します
- このアストロサイト媒介のメカニズムは 神経血管伝達の重要な要素です
関連する概念動画
Feedback Regulation of Calcium Concentration
3.5K
Calcium is an essential signaling molecule required for various cellular functions. Calcium pumps and ion channels on cell and organellar membranes, such as those on the endoplasmic reticulum (ER), regulate calcium concentrations inside the cell. They remain closed, keeping the cytosolic calcium levels low at a resting state.
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
3.5K
Antihypertensive Drugs: Action of Calcium Channel Blockers
768
Calcium ions are essential to contract smooth muscle cells in blood vessels. They enter these cells through voltage-dependent calcium channels, specifically L-type calcium channels in the cell membrane. These L-type calcium channels are integral to the excitation-contraction coupling process in smooth muscle. When a stimulus is received by smooth muscle cells, their membrane depolarizes. This alteration in membrane potential instigates the opening of L-type calcium channels. As a result,...
768
Ligand-Gated Ion Channel Receptor: Gating Mechanism
2.6K
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...
2.6K
Adrenergic Neurons: Neurotransmission
4.1K
Postganglionic sympathetic fibers (except those supplying the sweat glands) releasing noradrenaline or norepinephrine are called noradrenergic or adrenergic neurons. Noradrenaline, dopamine, adrenaline, or epinephrine are collectively called "catecholamines" as they contain a catechol moiety and an amine side chain. The five stages of neurotransmitter release involve their synthesis, storage, release, reuptake and metabolism.
Synthesis: Catecholamine synthesis requires tyrosine, which...
Synthesis: Catecholamine synthesis requires tyrosine, which...
4.1K
Adrenergic Receptors: β Subtype
2.0K
β-adrenoceptors have varied sensitivities towards adrenaline, noradrenaline, and isoprenaline. The order of agonist potency is as follows:
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors...
Isoprenaline > Adrenaline > Noradrenaline
Neurotransmitter binding to these receptors causes activation of adenylyl cyclase resulting in increased concentrations of cAMP and modulation of calcium ion channels within the cell. They are further classified into β1, β2, and β3 subtypes.
β1-adrenoceptors: β1-adrenoceptors...
2.0K
cAMP-dependent Protein Kinase Pathways
6.6K
Cyclic Adenosine Monophosphate (cAMP) is an essential second messenger that activates protein kinase A (PKA) and regulates various biological processes. A single epinephrine molecule binds to GPCR and activates several heterotrimeric G proteins, each stimulating multiple adenylyl cyclase, amplifying the signal, and synthesizing large numbers of cAMP molecules. Small changes in cAMP concentration affect PKA activity. The binding of four cAMP molecules induces a conformational change in PKA,...
6.6K


