陽子ゲートされたCa ((2+) 透過性TRPチャネルは,血栓不全を模倣した状態でミエリンを損傷する
Nicola B Hamilton1, Karolina Kolodziejczyk1, Eleni Kougioumtzidou1
1Department of Neuroscience, Physiology &Pharmacology, University College London, Gower St., London WC1E 6BT, UK.
Nature
|January 14, 2016
まとめ
脳内のミエリンに損傷を与えるが,NMDA受容体には影響しない. 代わりに,細胞内酸性の増加はTRPA1チャネルを活性化し,カルシウムレベルを上昇させ,ミエリンを損傷させ,TRPA1を治療標的として示唆する.
科学分野:
- 神経科学
- 細胞生物学
- 生物化学
背景:
- オリゴデンドロサイトは 脳の機能に不可欠な 骨髄膜を産生します
- 骨髄膜が損傷し,作用力の伝播を阻害する.
- この損傷は以前はN-メチル-D-アスパルテート (NMDA) 受容体の活性化に起因していた.
研究 の 目的:
- 低血圧期におけるオリゴデンドロサイト損傷のメカニズムを調査する.
- 細胞内カルシウム増加に関与するイオンチャネルを特定する.
- 白血病の潜在的治療目標を探るため
主な方法:
- 電気生理学では,膜の電流と細胞内イオン濃度 ([Ca2+]i, [Mg2+]i, [H2+]i) を測定する.
- TRPA1チャネルの薬学的な抑制と遺伝的ノックアウト
- TRPA1 阻害がある場合とない場合におけるミエリン損傷の評価
主要な成果:
- NMDAは,成熟したオリゴデンドロサイトにおける細胞内カルシウムを増加させなかった.
- 細胞外カリウムが増加し,カリウム伝導性が低下した.
- 細胞内アシドーシス ([H(+) iの上昇) は,TRPA1経路を通したカルシウムとマグネシウムの流入を引き起こし,ミエリン損傷を引き起こした.
- TRPA1 経路の阻害により,骨髄損傷が減少しました.
結論:
- 細胞内アシドーシスは,NMDA受容体ではなくTRPA1チャンネルを活性化します.
- TRPA1チャネルは白質血症の際にカルシウムとマグネシウムの流入を媒介する重要な媒介です.
- TRPA1を含むイオンチャネルは,白質不血症の治療に有望な治療対象となります.
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