长时间太空飞行后的大脑血管脉动性与脉冲压的变化和动脉硬性有关
Roxanne Fournier1, Danielle K Greaves1, J Kevin Shoemaker2
1Schlegel-UW Research Institute for Aging, Waterloo, Ontario, Canada.
Experimental physiology
|May 19, 2025
概括
太空飞行改变了大脑血液流动的脉动性. 从六个月的任务返回的宇航员显示中脑动脉脉动力增加,与动脉延伸能力降低和硬度增加有关.
科学领域:
- 心血管生理学心血管生理学
- 太空医学 太空医学
- 大脑血管动力学
背景情况:
- 中枢动脉硬化会提高下游的血液动力脉动,影响像大脑这样的器官.
- 长时间的太空飞行与减少常见动脉 (CCA) 延展性有关.
- 宇航员的脑血管脉动性仍然没有完全表征.
研究的目的:
- 为了研究从飞行前到6个月后太空飞行的脑血管脉动性变化.
- 探索宇航员动脉硬和脉动性之间的关系.
主要方法:
- 来自四项涉及27名宇航员的实验数据的二次分析 (20名男性,7名女性).
- 测量中脑动脉血液速度 (MCAv) 脉动性指数 (PI) 在卧卧状态下.
- 在队列的子集中评估了CCA延展性,β刚性和CCA波强度.
主要成果:
- 飞行后PImca的总体增加没有统计学意义 (P=0.060).
- 个人PImca变化与大动脉脉压 (r=0.51),β度 (r=0.54),CCA延展性 (r=-0.62) 相相关.
- 波强度分析表明,规范波反射减少 (P=0.07) 和前向压缩波幅和PImca (r=0.64) 之间的直接关系.
结论:
- 太空飞行后的PImca受心动脉延展能力降低的影响.
- 这些发现突显了宇航员动脉硬和脑血管脉动性之间的相互作用.
- 需要进一步的研究才能充分了解太空飞行的长期脑血管影响.
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