薬理学的ストレスタリウムスシンチグラフィーで,2-サイクロヘキシルメチリデネヒドラジノアデノシン (WRC-0470). 新型,短期間作用のアデノシンA2A受容体アゴニストである
1Department of Medicine, University of Virginia Health Sciences Center, Charlottesville 22908, USA. dkg2w@virginia.edu
Circulation
|October 1, 1996
まとめ
新しい選択性アデノシンA2A受容体アゴニストであるWRC-0470は,ストレス画像のために冠動脈を効果的に拡張し,副作用を引き起こすことはありません. これは,薬理学的ストレステストを受ける患者にとってより安全な代替案を提供します.
科学分野:
- 心臓病学 心臓病学
- 薬理学 薬理学とは
- メディカルイマージング (医学イメージング)
背景:
- アデノシンなどの薬理学的ストレス画像剤は,非選択的なアデノシン受容体刺激により重大な副作用を引き起こす可能性があります.
- これらの副作用には,低血圧,胸痛,気管支柱のなどがあり,特定の患者での使用を制限しています.
研究 の 目的:
- 新型,選択的なアデノシンA2A受容体アゴニスト (WRC-0470) を,薬理学的ストレス perfusion イメージングの潜在的なエージェントとして評価する.
- WRC-0470が非選択性アデノシン受容体アゴニストに関連する副作用なしに冠動脈血管拡張を誘発できるかどうかを判断する.
主な方法:
- 開胸犬にWRC-0470を投与し,投与量による冠動脈血管拡張と血液動力学的安定性を評価した.
- WRC-0470の血液動力学的反応と冠動脈血管拡張の比較と,誘発冠動脈狭窄症の犬におけるアデノシンとの比較.
- 心筋の欠陥を評価するために, perfusion imaging でピークストレスの 201T1 の注射を使用しました.
主要な成果:
- WRC-0470は,心拍数や血圧に影響を及ぼさずに,左側前下行 (LAD) と左側周回 (LCx) の冠動脈で用量依存の血管拡張を引き起こした.
- アデノシン投与は著しい低血圧をもたらし,その使用を制限しました.
- WRC-0470は低血圧なしでLCxの血流を大幅に増加させ, perfusion imagingはLAD狭窄症の犬のアンテロスペタル欠陥を明らかにしました.
結論:
- 選択的なアデノシンA2AアゴニストであるWRC-0470は,強力な短期間作用の冠動脈血管拡張剤です.
- WRC-0470は,薬理学的ストレス perfusion イメージングのための安全で効果的なエージェントとしての可能性を実証しています.
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