まとめ
エタノールは心臓に負のイノトロピック効果を及ぼし,これは通常,自律神経系によってマスクされます. この効果は,自律神経系が遮断されたときに明らかになる.
科学分野:
- 心臓病学 心臓病学
- 薬理学 薬理学とは
背景:
- 自律神経系は,心臓の機能に大きな影響を与えます.
- エタノールが心筋収縮に及ぼす直接的な影響は,特に自律的トーンが変化した状態では,完全に理解されていません.
研究 の 目的:
- 急性エタノール摂取が左心房機能に及ぼす影響を調査する.
- エタノールが,自律神経系の活動とは独立して,直接的な負のイノトロピー効果を発揮するかどうかを判断する.
- エタノールと自律性阻害による心臓の機能に対する相互作用を評価する.
主な方法:
- 9人の健康な被験者 (20〜35歳) のMモードエコーカルディオグラフィとシストリック時間間隔を利用した.
- プロプラノロールとアトロピンを静脈内投与して自律的ブロックを施した.
- コントロール期間中,自律的封鎖後,およびエタノール摂取後 (単独および封鎖とともに) の測定された心臓のパラメータ.
主要な成果:
- 自律的封鎖だけでは,心拍数と周囲の繊維の縮小の平均速度が増加しました.
- エタノール摂取だけで心臓機能の変化はほとんどなく,排泄前期と左心室排泄時間比 (PEP/LVET) はわずかに増加した.
- 結合されたエタノールと自律的封鎖は,環状繊維の縮小の平均速度を大幅に低下させ,PEP/LVETを増加させ,収縮率の低下を示した.
結論:
- 自律的封鎖は,心臓の収縮性を直接損なわない.
- 急性エタノール摂取だけでは,正常な個人の心臓機能に軽微な影響を及ぼします.
- エタノールは心臓に負のイノトロピー効果を発揮し,同情性およびパラシンパシー性活動によってマスクされ,自律性ブロック時に明らかになります.
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