在未成熟的子心脏中的预条件:KATP通道的作用
J E Baker1, P Holman, G J Gross
1Division of Cardiothoracic Surgery, Department of Pharmacology and Medical College of Wisconsin, Milwaukee, USA. jbaker@mcw.edu
Circulation
|March 9, 1999
概括
不成熟的心脏可以通过预先调节来保护免受伤害,但只有在没有从出生就暴露于慢性缺氧的情况下. 这种心脏保护作用涉及KATP通道.
科学领域:
- 心血管生理学心血管生理学
- 新生儿心脏病学 新生儿心脏病学
- 缺血预先调节 缺血预先调节
背景情况:
- 缺血预调提供了跨物种成年心脏的保护.
- 未成熟的心脏的预先条件的潜力,其持续时间和潜在的机制仍然不太了解.
研究的目的:
- 为了调查未成熟的心脏,在正常或慢性缺氧条件下,是否可以接受预先调节.
- 确定这种心脏保护作用的时间窗口和KATP通道的作用.
主要方法:
- 孤立的未成熟的子心 (7-10天大) 经过不同周期的缺血/再输血进行预调.
- 然后将心脏暴露在更长的缺血期中,通过左心室发育的压力来衡量恢复.
- 评估了KATP通道阻塞和不同的再输血时间的影响.
主要成果:
- 诺莫西克不成熟的心脏在一个预调节周期后显著恢复,三个周期没有额外的好处.
- 慢性缺氧不成熟的心脏没有表现出与非先决条件对照相比,先决条件的增强恢复.
- 当预先调节后的恢复期延长到30分钟时,心脏保护失去了.
- 在normoxic心脏中,KATP通道封锁取消了预条件效应.
结论:
- 来自normoxic环境的不成熟的心脏可以预先条件.
- 从出生开始暴露于慢性缺氧的未成熟心脏不能有效地预先条件.
- 该KATP通道涉及到normoxic不成熟心脏的预条件.
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