まとめ
胎児の羊の肺血管の発達は,耐性血管の数が妊娠年齢とともに増加することを示しています. これは,血管壁の厚さではなく,より高い血流とより低い抵抗を説明します.
科学分野:
- 心血管生理学 心血管の生理学
- 胎児の発達について
- 肺循環 肺循環について
背景:
- 胎児の羊が成熟するにつれて,肺の血流が増加し,血管抵抗が低下します.
- これに寄与する肺動脈の特定の形態学的変化は十分に理解されていません.
研究 の 目的:
- 妊娠年齢との関係で肺動脈の形態学的発達を図解する.
- 胎児の羊の肺の血管数と壁構造の変化を調査するために.
主な方法:
- 胎児の羊の妊娠年齢を問わず肺動脈血管を比較する方法を開発した.
- 肺動脈を貫通し,視覚化のためにインドインク混合物を注入しました.
- 中間幅と外径の比率を評価し,船の番号をシリアルセクションで数えた.
主要な成果:
- 第5世代レジスタンス血管の中間幅/外径比は,妊娠85~140日間で恒常 (0.16) でした.
- 右肺毎の第5世代と第6世代血管の総数は,妊娠年齢 (0.10 x 10^6から4.08 x 10^6) により有意に増加した.
- 単位体積あたりの血管密度も,妊娠期間に大幅に増加した.
結論:
- 成長する胎児の羊の肺血流の増加と血管抵抗の低下は,主に肺血管の総数の増加によるものです.
- 強化された血管運動反応性は,個々の血管壁の厚さの変化ではなく,より大きな総量の滑らかな筋肉に関連しています.
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