細胞内Ca2+,pHi,および収縮性に対する老化の影響,イシュケミアおよび再注射中の収縮性
1Department of Surgery, Harvard Medical School, Boston, MA.
Circulation
|November 1, 1992
まとめ
衰老は,イシュケミア中の細胞性カルシウム (Ca2+) の蓄積を増加させ,再注射後の心機能の低下につながります. 高齢の心臓は,成熟した心臓と比較して回復が低下し,高レベルのCa2+は機能的低下と相関しています.
科学分野:
- 心血管生理学 心血管の生理学
- 老化に関する研究
- イシュケミア・リパーフュージョン・ケガ
背景:
- 老化により,心筋膜が不血性および再注射性損傷に敏感になる.
- 細胞内カルシウム (Ca2+) と細胞内pH (pHi) などの重要な要因が関与しています.
研究 の 目的:
- 衰老が心筋不全および再注射性損傷に及ぼす影響を調査する.
- 細胞溶液Ca2+,pHi,および機械性能における年齢関連の変化を評価する.
主な方法:
- 成熟したおよび高齢のグループから隔離された浸透されたウサギの心臓を使用しました.
- 心臓はノルモサーミック・イシュケミアと再注射を受けた.
- サイトソリックCa2+とpHiは,光指標 (fura-2,BCECF) を使用して測定されました.
主要な成果:
- 高齢の心臓は,成熟した心臓と比較して,イシュケミア中に細胞溶液Ca2+の有意な増加を示しました.
- 両グループとも,イシュケミア中のpHiの類似した低下を経験しました.
- 左心室のピーク圧力の機能的回復は,成熟した心臓 (84%) と比較して高齢の心臓 (55%) で著しく低下しました.
結論:
- 老いた心臓は,イシュケミア中にCa2+の蓄積が増加し,機能回復の低下と相関しています.
- 高齢の心臓におけるCa2+の上昇は,アシドーシスのバッファリング能力の違いによるものではない.
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