心肌β-上腺素受体功能和高能酸盐在脑死亡中与心脏功能障碍相关的心脏功能障碍
H B Bittner1, E P Chen, C A Milano
1Department of General and Cardiothoracic Surgery, Duke University Medical Center, Durham, NC 27710, USA.
Circulation
|November 1, 1995
概括
大脑死亡导致显著的双心室功能障碍,特别是在右心室,影响心脏移植结果. 尽管β-上腺素受体活性增加,但这种情况仍然发生,这表明非缺血性损伤机制.
科学领域:
- 心脏病学 心脏病学
- 移植免疫学 移植免疫学
- 生理学 生理学 生理学
背景情况:
- 心脏移植后的心脏功能障碍是一个重要的临床问题.
- 移植前脑死亡 (BD) 期间的事件可能会导致心力衰竭.
- 在BD期间了解心肌变化对于改善移植成功至关重要.
研究的目的:
- 为了研究心脏功能和脑死亡后心肌中的生化变化.
- 评估心肌高能酸盐和BD后的β-上腺素受体系统.
- 为了确定BD对心室功能的影响和潜在的损伤机制.
主要方法:
- 利用经过验证的大脑死亡 (BD) 的狗模型.
- 仪器化的狗心来测量心室压力和体积关系 (PRSW).
- 在BD之前和之后评估β-上腺素受体 (BAR) 密度,腺酸环酶 (AC) 活性和心肌ATP/肌酸 (CP) 水平.
主要成果:
- 大脑死亡诱导了显著的缩双心脏功能障碍,对右心室 (RV) 的影响更为明显.
- 贝塔-上腺素受体密度和腺酸环酶活性在BD后显著上调.
- 心肌ATP和肌酸水平保持不变,这表明全球性缺血不太可能.
结论:
- 大脑死亡导致两个心室的显著缩功能障碍,对RV的影响更大.
- 观察到的BD后的RV功能障碍可能会导致心脏移植接受者的早期术后RV衰竭.
- 尽管心脏功能障碍发生了β-上腺素受体系统的升调,这表明与全球心肌缺血无关的复杂损伤途径.
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