アンジオテンシンIIは,ヒトの心臓線維芽細胞に多重なプロフィブロティック効果を発揮する
1Department of Medicine, Division of Endocrinology, Diabetes, and Hypertension, University of California at Los Angeles School of Medicine, CA 90024, USA.
Circulation
|March 15, 2000
まとめ
アンジオテンシンII (Ang II) は,ヒトの心臓細胞のAT1受容体を活性化し,心臓線維症を促進します. この研究では,Ang IIの役割が,AT ((1) 受容体シグナル伝達を通じて,線維細胞の結合と細胞外マトリックス蓄積を増加させることを明らかにしています.
科学分野:
- 心血管生物学 心血管生物学
- 細胞および分子医学は,細胞および分子医学である.
- 繊維症の研究 繊維症の研究
背景:
- アンジオテンシンII (Ang II) は心臓の改造と関連しており,プロフィブロティック効果があります.
- Ang II がヒトの心臓線維芽細胞に及ぼす直接的な影響を理解することは,心臓線維症の研究にとって極めて重要です.
研究 の 目的:
- Ang IIがヒトの心臓線維芽細胞に及ぼす直接的な細胞効果を調査する.
- 線維細胞の成長,細胞外マトリックス蓄積,粘着におけるAng IIの役割を決定する.
- これらの効果を媒介する特定のAng II受容体を特定する.
主な方法:
- ヒトの心筋線維芽細胞は,心臓の膨らんだ部分から分離された.
- 細胞はAng IIおよび特定の受容体対抗剤 (イルベサタン,PD 123319,ディヴァリニル) で治療されました.
- アッセイには,ミトゲン活性化タンパク質キナーゼ活性,DNA合成,mRNAレベル (TGF-β1,ラミニン,フィブロネクチン,PAI-1),およびフィブロブラストのコラーゲンへの結合の測定が含まれていました.
主要な成果:
- Ang IIは,繊維細胞のDNA合成,TGF-β1,ラミニン,およびフィブロネクチンのmRNAレベルを著しく増加させた.
- Ang IIはプラズミノゲンアクティベーターインヒビター-1の発現と心臓の線維芽細胞がコラーゲンに結合することを強化しました.
- これらの効果は,イルベサルタンによって阻害されたため,AT(1) 受容体を通してのみ媒介された.
結論:
- ヒトの心臓細胞におけるAng IIによるAT(1) 受容体の活性化は,心臓線維症を促進する.
- Ang IIは,プラズミノゲン活性化剤阻害剤-1発現を刺激する新しい役割を果たしています.
- Ang IIは,心臓の線維細胞がコラーゲンに付着することを強化し,線維細胞のプロセスに寄与します.
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