ラットにおけるリラクシンによる心臓効果
H Kakouris1, L W Eddie, R J Summers
1Howard Florey Institute of Experimental Physiology and Medicine, University of Melbourne, Parkville, Australia.
Lancet (London, England)
|May 2, 1992
まとめ
合成ヒトリラクシン (hRlx-2) は,心拍数とネズミの心房の収縮性を著しく増加させます. このホルモンは強力な心臓効果を発揮し,心臓の特定のリラクシン受容体に直接作用する可能性があります.
科学分野:
- 心血管生理学 心血管の生理学
- エンドクリノロジー エンドクリノロジー
背景:
- リラキシンは主に妊娠ホルモンとして知られています.
- 豚のリラクシンは,特にネズミの心拍数を増加させる心臓の効果を示しています.
研究 の 目的:
- 合成ヒトゲン-2リラクシン (hRlx-2) の心臓への影響を調査する.
- 単離されたネズミの心房におけるhRlx-2のクロノトロピクおよびイノトロピク効果を決定する.
主な方法:
- 単離されたネズミの心房を用いた in vitro 実験で使用された.
- 合成のhRlx-2が心臓機能に及ぼす濃度依存の影響を評価した.
主要な成果:
- 合成のhRlx-2は,自発的に鼓動する右心房 (EC50 = 0.09 nmol/l) に対する濃度依存の陽性クロノトロプ効果を示した.
- 合成のhRlx-2は,電気駆動の左心房に濃度依存の陽性イノトロピー効果を示した (EC50 = 0.31 nmol/l).
- hRlx-2の効力は,ネズミの心房におけるエンドセリン,アンジオテンシンII, (-) - アイソプレナリンを上回った.
結論:
- ヒューマン・リラクシン (hRlx-2) は,心臓に強力なプラスのクロノトロピーおよびイノトロピー効果を持っています.
- これらの心臓効果は,リラクシン受容体への直接作用によって媒介される可能性が高い.
- リラキシンの役割は,妊娠を超えて,心臓の直接的な調節に及ぶ可能性があります.
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