発血性心筋病変症の患者における心筋細胞の構造再構築
A M Gerdes1, S E Kellerman, J A Moore
1Department of Anatomy, University of South Florida, College of Medicine, Tampa 33612.
Circulation
|August 1, 1992
まとめ
缺血性心筋症 (ICM) では,心臓腔の膨張は主に心筋細胞の伸びによるもので,滑りによるものではない. 筋細胞の形状の変化は,心臓壁のストレス増加に寄与する.
科学分野:
- 心血管生物学 心血管生物学
- 心臓のリモデリング
- 心不全 病理生理学 心不全 病理生理学
背景:
- 慢性発血性心疾患は,心室の膨張と閉塞性心不全を引き起こし,発血性心筋病 (ICM) と呼ばれる状態を引き起こす可能性があります.
- ICMにおけるこの心房の膨張に寄与する心筋細胞の形状の特定の変化は,以前は理解されていませんでした.
研究 の 目的:
- 缺血性心筋病症の文脈における心筋細胞の寸法と形状の変化を調査する.
- 細胞内変化 (肌細胞の伸び) または細胞外変化 (肌細胞の滑り) がICMにおける腔の膨張に起因するかどうかを判断する.
主な方法:
- 隔離された左心室筋細胞は,ICMの患者の心臓のエクスプラントと,正常な冠動脈 (NCA) の不衰のドナー心臓から得られた.
- 長さと幅を含む肌細胞の寸法が定量的に評価され,ICMとNCAのグループ間で比較されました.
主要な成果:
- ICM心臓からの筋細胞は,NCA心臓からの筋細胞と比較して,かなり長 (40%増加) であり,長さ/幅の比 (49%増加) が大きかった.
- 筋細胞の幅やサルコメアの長さの有意な差は2つのグループでは観察されなかった.
- 観察された筋細胞長さの増加は,ICMの患者における末端ダイアストリック直径の記録された増加を密接に反映しています.
結論:
- 細胞内変異である肌細胞長さの増加は,不全性心筋症における腔拡張の主な要因である.
- 筋細胞の形状の不適切な改造,特に長さと幅の比の増加は,ICMにおける心臓壁の高圧を悪化させる可能性があります.
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