インビボ酵素占有率の決定 阻害剤解離運動
Dennis J Murphy1, Yangsi Ou1, Danielle H Euler1
1In Vitro Pharmacology, ‡Bone Biology, and §In Vivo Pharmacology, Merck Research Laboratories , West Point, Pennsylvania 19486, United States.
Journal of the American Chemical Society
|August 25, 2015
まとめ
新しい方法では,ゆっくり解離する運動学を用いて,薬物のターゲット占有率をin vivoで定量的に測定します. このアプローチは特殊な反応剤を避け,ウサギの骨組織におけるキャセプシンK阻害剤の占有率を評価することで,薬剤発見のための一貫した,信頼できるデータを提供します.
科学分野:
- 薬理学について
- 生物化学
- 薬物の発見
背景:
- 薬の有効性を予測するには,インビボ標的占有率の評価が不可欠です.
- 目標占有率の評価のための現在の方法は,技術的に難しいことが多く,定量的精度が欠けている.
研究 の 目的:
- 特殊な反応剤を用いることなく,生体内の酵素占有率を決定するための単純で定量的な方法を開発する.
- この方法を用いて,骨組織におけるキャセプシンK (Cat K) 阻害剤の占有量を測定する.
主な方法:
- 遅い解離運動を用いたジャンプ・稀解法を開発した.
- 阻害剤の解離後の基質の周回をモニタリングすることで酵素の活性を分析した.
- 初期と安定状態の反応率 (vi/vs) の比率から占有率を計算する.
主要な成果:
- この方法は,ウサギの股関節骨組織におけるCat K阻害剤の占有量を定量的に決定した.
- カットK阻害剤MK-0674の投与により,投与量に依存する占用性が実証され,1. 0 mg/ kgでほぼ完全な占用性が達成された.
- この測定法により,標的組織におけるCat Kの総濃度も測定することができました.
結論:
- ゆっくり解離する運動学は,体内の標的占有率の評価に堅実で定量的なアプローチを提供します.
- この方法は,同じアッセイ内で占有および非占有酵素データを得ることで一貫性を高めます.
- これらの発見は,酵素阻害剤の評価のための薬剤発見におけるこの方法の有用性を支持する.
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