在人体内乳腺动脉和软静脉之间,内皮衍生的高极化因子介导的高极化和氧化释放的差异
1Cardiovascular Research Laboratory, Grantham Hospital, University of Hong Kong, Hong Kong, China.
Circulation
|November 18, 2000
概括
内部乳腺动脉 (IMA) 释放更多的氧化 (NO) 并表现出更大的内皮衍生超极化因子 (EDHF) 介导的超极化,而不是静脉 (SV). 这些发现表明IMA的机制.
科学领域:
- 血管生物学 血管生物学
- 心血管外科心血管外科
- 生理学 生理学 生理学
背景情况:
- 内部乳腺动脉 (IMA) 的氧化 (NO) 释放量大于软静脉 (SV).
- 之前的研究表明这基于放松,但直接的NO和EDHF介导的超极化没有被测量.
- 这项研究直接量化了IMA和SV中NO和EDHF介导的超极化.
研究的目的:
- 直接测量内部乳腺动脉 (IMA) 和软静脉 (SV) 中的氧化 (NO) 和内皮衍生的超极化因子 (EDHF) 介导的超极化.
- 为了比较IMA和SV之间的NO释放和超极化.
- 为了研究IMA移植的优越透光度的生理基础.
主要方法:
- 来自冠状动脉手术患者的血管细分 (IMA,n=46;SV,n=61) 用器官腔进行了研究.
- 细胞内玻璃微电极测量了超极化.
- 对NO敏感的电极测量了对乙胆和布拉迪基宁的反应中NO的释放.
- 药理学剂 (N(G) - - 尼特罗-L-阿尔金因,印米他辛,氧血球) 用于区分NO和EDHF通路.
主要成果:
- IMA光滑肌细胞的静止膜潜力 (-58 mV) 比SV (-62 mV) 高.
- 在对乙胆和布拉迪基宁的反应中,以EDHF为媒介的超极化在IMA中明显大于SV.
- 基础NO释放在IMA (16.8nmol/L) 中显著高于SV (9.9nmol/L).
- 在IMA中,由乙胆和布拉迪基宁诱导的NO释放的持续时间更长.
结论:
- 内部乳腺动脉 (IMA) 显示出明显更大的基底氧化 (NO) 释放和EDHF介导的高极化,相比于静脉 (SV).
- 在IMA中,刺激NO释放的持续时间也更长.
- 这些独特的血管性质可能有助于在冠状动脉绕道手术中观察到IMA移植的优异长期通透率.
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