在左心室脱差后的阴道心肺反射
1Department of Medicine, Medical College of Virginia/Virginia Commonwealth University, Richmond.
Circulation
|October 1, 1994
概括
来自左心室 (LV) 的 afferent神经纤维被中断,以研究它们在调节交感神经活动 (RSNA) 中的作用. 输入LV输入的损失具有适度的影响,表明其他心肺受体可以补偿.
科学领域:
- 心血管生理学心血管生理学
- 自主神经系统的调节规则
- 脏生理学 脏生理学
背景情况:
- 主要来自心室的 afferent神经纤维被心脏事件中断,如移植和心肌梗塞.
- 在心脏移植和心肌梗塞后观察到由阴道 afferent 纤维介导的心肺反射异常.
- 这些反射异常和心室脱差之间的关系尚不清楚.
研究的目的:
- 研究左心室 (LV) 脱差对心肺反射控制交感神经活动 (RSNA) 的影响.
- 评估 LV 虚 afferent 输入在调节 RSNA 对血液动力学变化的反应中的作用.
主要方法:
- 在狗中使用醇麻醉和阴脉动脉变质来研究RSNA的阴脉心肺反射控制.
- 测量左心脏压力 (LAP) 和RSNA对出血和体积膨胀的反应,在LV与脱差之前和之后.
- 利用声微观测来评估LV心肌段长度和冠心内尼古丁来确认分离.
主要成果:
- 在体积膨胀过程中,LV脱差轻微减弱了阴道心肺反射灵敏度 (P < .05).
- 在LV脱差后的出血期间,没有观察到反射灵敏度的显著变化.
- 冠内尼古丁未能抑制RSNA分离后,证实了有效的心室分离.
结论:
- 从LV中断阴道 afferent输入只对通过阴道心肺反射控制RSNA产生适度的影响.
- 性心肺反射表现出显著的冗余性,肺和其他心室受体补偿LV afferent输入损失.
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