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高用量アスピリンは,トロンビン生成を伴う切断誘発性血小板反応を抑制する
C P Ratnatunga1, S F Edmondson, G M Rees
1Department of Cardiothroracic Surgery, St. Bartholomew's Hospital Medical School, London.
Circulation
|March 1, 1992
まとめ
アスピリンの75mg/日投与は,手術後の血小板過剰反応を完全に防ぐことはできませんでした. 切断誘発性血小板反応を抑制するために,より高いアスピリン用量 (300 mg/日以上) が必要であり,これは,血栓糖抑制を超えたメカニズムを示唆する.
科学分野:
- 心血管薬理学について
- 血小板生物学 血小板生物学について
背景:
- サイクロオキシゲネーゼ抑制とプロスタグランジン合成によるアスピリンの作用の確立されたメカニズムは,アスピリンのすべての効果を説明するのに不十分です.
- アスピリンの総合的な薬理学的作用に関する未回答の疑問が残っています.
研究 の 目的:
- 冠動脈バイパス手術後の患者の血小板活性に対する異なるアスピリン用量の影響を調査する.
- 切断誘発性血小板反応に対するアスピリンの影響を調べるために.
主な方法:
- 血小板トロンボキサン形成と全血凝集の評価は,手術後の75mg/日アスピリンを服用した294人の患者で評価された.
- 患者と健康な対照群の血小板反応性の比較.
- 90人の患者でアスピリンの投与量を300mg/日まで増加させ,反応性を再テストした.
- 正常な被験者に単回600mgのアスピリンを投与し,シーア誘発性血小板反応を評価した.
主要な成果:
- 75 mg/日アスピリンは,対照群と比較して有意な過剰反応を示した患者の80%で,血小板血栓素の形成を不完全に防止しました.
- アスピリンを1日300mgに増加させると,血小板の反応性が著しく低下した (p = 0.0008).
- 75 mg/日投与を継続した患者は,血小板反応性の変化を示さなかった.
- 一回600mgのアスピリンは,健康な被験者におけるシーアー誘発性血小板反応を著しく抑制しました.
結論:
- 切断力に対する血小板の反応に対するアスピリンの効果は,より高い用量 (300 mg/日以上) を必要とします.
- この切断誘発効果のメカニズムは,血栓素形成に対するアスピリンの干渉と異なる可能性が高い.
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