在人类冠状动脉和外周循环中,L-氨酸的运输
S E S Miner1, A Al-Hesayen, S Kelly
1Mount Sinai Hospital and University Health Network, University of Toronto, Ontario, Canada.
Circulation
|March 10, 2004
概括
这项研究表明,氧化合成酶 (NOS) 活性受血中阿尔金因水平的影响,乙胆刺激阿尔金因吸收,N(G) -单甲基-L-阿尔金因 (L-NMMA) 诱导阿尔金因在人体冠状动脉循环中的流出.
科学领域:
- 心血管生理学心血管生理学
- 生物化学 生物化学
- 医学研究 医学研究
背景情况:
- 氧化合成酶 (NOS) 从氨酸中合成氧化 (NO).
- 细胞内阿尔金因水平通常表明NOS活性独立于血阿尔金因.
- 然而,血中阿尔金宁的增加可能与NOS活动的增加有关.
研究的目的:
- 调查人类冠状动脉和外周循环中的阿基宁运输.
- 了解血中阿尔金因与NOS活性之间的关系.
主要方法:
- 在31名患者中,输注质量标记的15N2-氨酸到稳定状态.
- 心脏导管和冠状动脉鼻腔导管的放置.
- 在静止状态下和在乙胆和L-NMMA输注期间测量跨心脏15N2-氨酸梯度.
主要成果:
- 在静止状态下没有检测到阿基尼因梯度.
- 乙胆输液诱导了显著的氨酸梯度,表明NOS刺激增强了氨酸的运输 (11.7%的分数提取).
- 输入L-NMMA导致负梯度,这表明通过载体介导的转刺激 (20.5%的分量产量) 产生了阿尔金宁流量.
结论:
- 稳态15N2-氨酸是一种用于研究跨器官L-氨酸梯度的新工具.
- 这种方法有助于理解L-氨酸的运输机制.
- 它提供了对内皮和NOS功能障碍机制的洞察.
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