ブシンドロロルの部分的アゴニスト活動は,ヒトβ1-アドレナゲン受容体の活性化状態に依存しています
Christoph Maack1, Michael Böhm, Lydia Vlaskin
1Klinik und Poliklinik für Innere Medizin III, Universität des Saarlandes, Homburg/Saar, Germany.
Circulation
|July 9, 2003
まとめ
ブシンドロロルは,ヒトのβ1-アドレナリン受容体 (β-ARs) の部分的アゴニストとして作用する. 衰弱した心臓におけるその活動は受容体活性化状態によってマスクされていますが,メトプロロールの前治療後に明らかになります.
科学分野:
- 薬理学 薬理学とは
- 心血管科学の研究について
- 分子生物学は分子生物学である.
背景:
- 心不全による死亡率を低減するブシンドロロルの失敗は,他のベータブロッカーと対照的です.
- この不一致は,ベータアドレナジック受容体 (β-ARs) でブシンドロロルの部分的アゴニスト活性に起因する可能性があります.
- ブシンドロロルの内在的活性に関する以前の研究では,種または組織特異のβ-AR活性化状態による可能性のある矛盾した結果が得られた.
研究 の 目的:
- ブシンドロロルの内在的活性を調べるために.
- 種の違いや異なるβ-AR活性化状態が,相反するブシンドロールの有効性データを説明するかどうかを判断する.
- ヒトの心筋不全におけるブシンドロールのメカニズムを明らかにする.
主な方法:
- ヒトβ1-AR過剰発現の孤立したマウスの心房に対するブシンドロールの効果を評価した.
- 失敗する人間の心房筋のストライプにおける収縮の力に対するブシンドロールの影響を評価した.
- ミオカルディアル製剤におけるメトプロロールまたはイソプロテレノールによる前処理後のブシンドロールの効果を調査した.
- ベータ-AR活性化を評価するために,フォルスコリン反応と相関するイノトロピック効果.
主要な成果:
- ブシンドロールは,マウスの心房でビート周波数を増加させ,ヒトβ1-ARsを過剰に発現させ,プロプラノロールによってブロックされる効果をもたらしました.
- 発心筋不全のヒトでは,ブシンドロールは基礎条件下では収縮力を変化させなかった.
- メトプロロールの予備治療は,ヒトの心筋不全においてブシンドロールの有意な陽性無otropic効果を明らかにしました.
- イソプロテレノールによる前治療は,不発症の心筋膜にXamoterolの陽性なイノトロピック効果を無効にしました.
- ブシンドロールとシャモテロールのイノトロピック効果は,フォルスコリン反応と逆相関していた.
結論:
- ブシンドロールは,ヒトβ1-AR.で部分的アゴニストです.
- 人間の衰弱した心臓では,ブシンドロールの部分的アゴニズムが,ベータ-AR活性化状態が上昇した状態によってマスクされています.
- メトプロロールの予備治療は,ヒトの心筋不全におけるブシンドロールの部分的アゴニスト作用を明らかにする.
- ブシンドロロルの部分的アゴニスト活動は,ヒトβ1-AR.の活性化状態に依存しています.
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