ブルガダ症候群の現象型が男性に優位であることを示すイオンと細胞の基礎
José M Di Diego1, Jonathan M Cordeiro, Robert J Goodrow
1Masonic Medical Research Laboratory, Utica, NY 13501-1787, USA.
Circulation
|October 9, 2002
まとめ
ブルガダ症候群は,男性の右心室に強い電流があるため,男性に多く見られる. この研究では,男女間のアクションポテンシャル・ノッチとイオンチャネル機能の違いが見つかりました.
科学分野:
- 心臓病学 心臓病学
- 電気生理学 電気生理学
- 遺伝学 遺伝学とは
背景:
- ブルガダ症候群は,低浸透性で自己相性支配的な遺伝を示しています.
- 臨床的な表現は,遺伝的伝播が均等であるにもかかわらず,男性では女性よりも有意に多く見られる.
- ブルガダ症候群の発現におけるこの性差の根本的な原因は不明である.
研究 の 目的:
- 男性の右心室内膜のより顕著なアクションポテンシャル・ノッチが,ブルガダ症候群における性差に寄与するという仮説を検証する.
- 男性と女性の右心室内膜の電気生理学的特性を比較する.
主な方法:
- 電気生理学的な研究は,犬の表心臓組織のスライス,動脈に浸透されたケイジ製剤,および男性と女性の心臓から分離された表心臓筋細胞で行われました.
- フェーズ1の振幅,電流密度,動力学を含むアクションポテンシャル特性を測定した.
- 薬理学的介入 (ピナシジル,テルフェナジン) は,観察された電気生理学的差異の機能的結果を評価するために使用されました.
主要な成果:
- 男性の右心室内膜は,女性と比較して,アクションポテンシャル第1相の振幅が著しく小さかった.
- current density (電流密度) とその時間常数 (時間常数) は,男性と女性RVエピカルディアル細胞の比較で,女性RVエピカルディアル細胞の比較で,著しく小さかった.
- 薬剤は,アクションポテンシャルドームと男性組織への再侵入により顕著な効果を誘発し,心室不律症の発生率が高かった.
結論:
- 発見は,男性におけるより顕著なI (to) 流が,ブルガダ症候群で観察された性優位性に寄与することを示唆しています.
- 右心室内膜におけるこれらの性別電気生理学的差異は,ブルガダ症候群の異なった臨床表現の根底にある可能性があります.
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