液体流动刺激培养的人体内皮细胞的组织等离子素激活剂分泌
S L Diamond1, S G Eskin, L V McIntire
1Rice University, Biomedical Engineering Laboratory, Houston, TX 77251.
概括
动脉壁剪切应力显著增加了内皮细胞的组织等离子素激活剂 (tPA) 分泌. 静脉剪切应力和所有水平的等离子原激活剂抑制剂,类型1 (PAI-1) 分泌没有受到影响.
科学领域:
- 心血管生物学心血管生物学
- 血液动力学 血液动力学
- 内皮细胞的功能是内皮细胞功能.
背景情况:
- 血流动力学,特别是壁切应力,越来越多地被认为是内皮细胞功能的关键调节者.
- 纤维分解性蛋白质,如组织塑原激活剂 (tPA) 和1型塑原激活剂抑制剂 (PAI-1),在维持血管通透性方面发挥着至关重要的作用.
- 了解机械力如何影响这些蛋白质的表达,对于理解血管健康和疾病至关重要.
研究的目的:
- 研究不同程度的生理壁切削应力对人体内皮细胞分泌tPA和PAI-1的影响.
- 要确定剪切应力是否对tPA和PAI-1的分泌有不同的影响.
主要方法:
- 培养的人体内皮细胞被暴露于受控水平的壁切应力,包括静脉 (4dynes/cm2) 和动脉 (15和25dynes/cm2) 条件.
- 在每个剪切应力条件下,测量了tPA和PAI-1的分泌速率.
主要成果:
- 暴露于静脉剪切应力 (4dynes/cm2) 并没有改变tPA或PAI-1分泌率.
- 动脉剪切应力为15dynes/cm2和25dynes/cm2,与基数相比,tPA分泌率显著增加,分别是2.1倍和3.0倍.
- 在整个切应力测试的生理范围中,PAI-1分泌没有受到影响.
结论:
- 壁切压力,特别是在动脉水平,是内皮细胞tPA分泌的重要调节者.
- 血管系统内的纤维解质平衡可能由血液动力学力调节,动脉剪切应力通过增加tPA释放促进更纤维解质状态.
- 在测试的生理范围内,PAI-1分泌似乎独立于剪切应力.
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