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Analytical Techniques for Assaying Nitric Oxide Bioactivity
Published on: June 18, 2012
氧化通过将氧化合成酶异型体的空间限制来调节心脏
Lili A Barouch1, Robert W Harrison, Michel W Skaf
1Department of Medicine (Cardiology Division), The Johns Hopkins Medical Institutions, Baltimore, Maryland 21287, USA.
Nature
|March 22, 2002
概括
氧化合成酶 (NOS1和NOS3) 在心脏功能中发挥着不同的作用. 这些酶的空间定位影响心脏收缩性和结构,NOS1和NOS3介导独立的效应.
科学领域:
- 心血管生理学心血管生理学
- 分子心脏病学分子心脏病学
- 细胞信号传输 细胞信号传输
背景情况:
- 氧化 (NO) 合成酶的亚细胞局部化对于NO信号传递至关重要.
- NO对心肌收缩率的影响是可变的,影响L型Ca2+通道和SR Ca2+释放.
- 特定的NO合成酶异型 (NOS1和NOS3) 在心脏中具有不同的亚细胞点.
研究的目的:
- 研究NO合成酶异型体在调节心脏功能的空间限制的作用.
- 确定NOS1和NOS3对心肌收缩性,结构和对β-上腺刺激的反应的独立和联合作用.
- 阐明NOS1和NOS3影响Ca2+处理和心脏重塑的机制.
主要方法:
- 使用了NOS1缺陷,NOS3缺陷和NOS1/3双淘汰赛小鼠模型.
- 评估心肌收缩性和内回应.
- 检查了sarcoplasmic网膜 (SR) 的Ca2+释放和L型Ca2+通道功能.
- 在淘汰赛小鼠中评估心脏结构,增高和血压.
主要成果:
- 洞穴中的NOS3分离通过调节L型Ca2+通道来抑制β-上腺素诱导的收缩性.
- 针对SR的NOS1促进了通过氨酸受体 (RyR) 介导的Ca2+释放的收缩性.
- NOS1缺乏抑制了收缩性;NOS3缺乏增强了收缩性,与SR Ca2+释放的相互变化相对应.
- 无论是NOS1-/-还是NOS3-/-小鼠都表现出与年龄相关的高血压;只有NOS3-/-小鼠是高血压的.
- 双重淘汰赛小鼠显示抑制了β-上腺素反应和添加性心室重塑.
结论:
- NOS1和NOS3的空间定位决定了它们在心脏收缩性中的对立作用.
- NOS1和NOS3对心脏结构和功能产生独立的,有时是对抗性的影响.
- 针对特定的NO合成酶异型,为心血管疾病提供了潜在的治疗策略.
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