格利本克拉米德在麻醉的犬类心肌中对抗腺氨酸A1受体介导的心脏保护
1Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee 53226.
Circulation
|July 1, 1993
概括
刺激腺A1受体可以保护心脏免受重复血流阻塞引起的麻醉. 这种保护作用可能涉及ATP依赖的K通道 (KATP),这表明缺血性心脏病的潜在治疗点.
科学领域:
- 心脏病学 心脏病学
- 药理学 药理学是指药理学的学科.
- 生理学 生理学 生理学
背景情况:
- 心肌麻醉是一种后缺血性功能障碍.
- 腺素受体在缺血期间在心脏功能中发挥作用.
- 特定的腺受体亚型及其与麻醉中KATP通道的相互作用仍然不清楚.
研究的目的:
- 为了研究腺在心肌震惊中在重复的冠状动脉封闭后的作用.
- 为了确定涉及的特定腺受体亚型 (A1或A2).
- 为了检查腺A1受体和依赖ATP的K通道 (KATP) 之间的相互作用.
主要方法:
- 在麻醉的狗身上进行了研究,这些狗经历了重复的冠状动脉封闭和再流.
- 区域性心脏功能使用声微米测量进行评估.
- 选择性腺A1受体激活剂 (CPA) 和对抗剂 (DPCPX),A2受体激活剂 (CGS 21680),和KATP通道阻断剂 (glibenclamide) 被使用.
主要成果:
- CPA的使用改善了心脏功能恢复,而DPCPX则使其恶化.
- 氨酸A2受体激活剂CGS 21680没有显著的影响.
- 格利本克拉米德消除了CPA的保护作用,表明KATP通道的参与.
结论:
- 心肌腺A1受体刺激,特别是在缺血早期,提供心脏保护,防止重复性闭塞.
- 这种心脏保护似乎部分通过对草甘胺敏感的机制进行介导,可能涉及KATP通道的开放.
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