周期性核酸フォスフォディエステラーゼ5型の活性により,運動中に心筋が過剰に浸透した部分への血流が制限されます
1Department of Medicine, Division of Cardiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA.
Circulation
|January 11, 2000
まとめ
PDE5阻害剤であるシルデナフィルは,運動中に冠動脈を広げることで,不全性心臓への血流を増加させます. この発見は,冠動脈狭窄と心筋 perfusion にその影響を理解するために重要です.
科学分野:
- 心血管生理学 心血管の生理学
- 薬理学 薬理学とは
背景:
- 酸化窒素 (NO) は,フォスフォディエステラーゼ (PDEs) によって調節されるcGMP経由の血管拡張を媒介する.
- PDE5阻害剤であるシルデナフィルは,冠動脈をリラックスさせます.
- この研究では,正常な心と不血性心における運動中の冠動脈の血流に対するシルデナフィルの影響を調査しています.
研究 の 目的:
- シルデナフィルの冠動脈の血流と血液動力学への影響を評価する.
- 運動中の正常および不血症の条件下でのシルデナフィルの有効性を評価するために.
主な方法:
- 慢性的に計測された犬を活用した.
- シルデナフィルの投与量 (2 mg/kg PO).
- 休息とトレッドミルの運動中の冠動脈の血流と血動力学を測定し,誘発された冠動脈狭窄症となく.
主要な成果:
- シルデナフィルは,正常な犬の静止冠動脈の血流をわずかに増加させた.
- 狭窄状態での運動は,冠動脈の血流を著しく低下させた.
- シルデナフィルは,運動中に缺血領域の血流を増加させた.
結論:
- シルデナフィルのPDE5阻害は冠動脈の抵抗血管を広げます.
- シルデナフィルは,静脈狭窄の存在下での運動中に缺血性心筋への血流を高めます.
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