心筋のベータアドレナジック受容体機能と,脳死における高エネルギーリン酸の関連心機能障害
H B Bittner1, E P Chen, C A Milano
1Department of General and Cardiothoracic Surgery, Duke University Medical Center, Durham, NC 27710, USA.
Circulation
|November 1, 1995
まとめ
脳死は,特に右心室の重要な二心房機能不全を引き起こし,心臓移植の結果に影響を与えます. これは,ベータアドレナゲン受容体の活性が増加したにもかかわらず発生し,非発血性損傷メカニズムを示唆しています.
科学分野:
- 心臓病学 心臓病学
- 移植免疫学 移植免疫学
- 生理学 生理学とは
背景:
- 心臓移植後の心臓機能不全は,重要な臨床問題である.
- 移植前の脳死 (BD) 中の出来事は,心不全に寄与する可能性があります.
- BD中の心筋の変化を理解することは,移植の成功を改善するために不可欠です.
研究 の 目的:
- 脳死後の心臓機能と心臓筋の生化学的変化を調査する.
- BD. の後に心筋高エネルギーリン酸とβ-アドレナジック受容体システムを評価する.
- 静脈動脈が心房の機能に与える影響と潜在的傷害メカニズムを決定する.
主な方法:
- 脳死 (BD) の検証された犬のモデルを利用した.
- 器具付き犬の心臓は,心室の圧力と体積の関係 (PRSW) を測定します.
- ベータアドレナリン受容体 (BAR) 密度,アデニラートサイクラゼ (AC) 活性,および心筋ATP/クレアチンフォスファート (CP) レベルをBD前後に評価した.
主要な成果:
- 脳死は,右心室 (RV) により顕著な影響を及ぼし,シストリック双心室機能不全を誘発した.
- ベータアドレネルジック受容体密度とアデニラートサイクラース活性が,BD後,著しく上位調節された.
- 肌動脈ATPとクレアチンフォスファートのレベルは変化せず,全身性イシュケミアの可能性は低いことを示唆した.
結論:
- 脳の死は,両心室の重要なシストリック機能不全につながり,RVにより大きな影響を及ぼします.
- 観察されたBD後のRV機能障害は,心臓移植受容者の早期の術後のRV不全に寄与する可能性があります.
- ベータ・アドレナージック受容体システムの上調は,心臓機能不全にもかかわらず発生し,全身性心筋不全と関係のない複雑な損傷経路を示唆する.
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