高エネルギーリン酸と乳酸の放出に対する反応は,長期にわたる地域性不血症 in vivo の間に発生する
S Schaefer1, G G Schwartz, J A Wisneski
1Department of Medicine, VA Medical Center, San Francisco, Calif.
Circulation
|January 1, 1992
まとめ
冬眠状態の心筋は,細胞活性を維持するために必要なエネルギーを減らす. 長期のイシュケミアでは,高エネルギーリン酸は血流とともに減少し,乳酸酸と酸化は部分的に改善し,イシュケミアの減少を示します.
科学分野:
- 心臓病学 心臓病学
- バイオケミストリー バイオケミストリー
- 生理学 生理学とは
背景:
- 持続的な心筋動脈不全,または心筋動脈不全,または心筋動脈不全.
- 冬眠状態で冬眠する.
- 心筋筋は,エネルギー需要を下げることによって,細胞の生存能力を保ちます.
- 以前の研究では,乳酸代謝と細胞内リン酸の反応が,イシュケミア中に多様であることが示されましたが,同一の流れ条件ではそうではありません.
研究 の 目的:
- 長期のイシュケミア中の高エネルギーリン酸塩と乳酸塩の代謝反応を調査する.
- これらの代謝変化を心筋の血流と機能と相関させるため.
主な方法:
- 31P核磁気共鳴スペクトロスコーピーを利用して,胸を開けた12匹のブタに試験を行った.
- 地域性イシュケミアの2時間間に測定された下腸内臓血流,セグメント縮小,高エネルギーリン酸 (ATP,PCr),および乳酸の放出.
- 缺血期を通してpHの変化をモニタリングした.
主要な成果:
- 下腸内心臓の血流とセグメントの縮小は,イシュケミア中に著しく減少しました.
- ATP,フォスフォクレアチン (PCr),PCr/Pi比は,血流に並行して減少した.
- 乳酸の放出は当初増加し,その後減少し,酸化 (pH) は時間の経過とともに部分的な改善を示した.
結論:
- 高エネルギーリン酸塩のレベルは,持続性イシュケミア中の血流と心臓機能と相関しています.
- 乳酸酸の産生と酸化は部分的に軽減され,エネルギー需要の減少が心筋の保存に役立つという仮説を裏付けます.
- これらの発見は,エネルギー需要の減少が冬眠状態の心筋膜のイシュケミアの減少に寄与することを示唆しています.
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