在有意识的狗中,物质P对全身和冠状动脉床的不同影响
Y Nakamura1, R Parent, M Lavallée
1Department of Physiology, Faculty of Medicine, University of Montreal Canada.
Circulation
|July 1, 1991
概括
物质P会导致全身血管扩张,但矛盾的是,在有意识的狗中会收缩冠状动脉. 这种是这种.
科学领域:
- 心血管生理学心血管生理学
- 药理学 药理学是指药理学的学科.
背景情况:
- 以前的研究表明,物质P (SP) 是麻醉动物的血管扩展剂.
- 冠状动脉血管扩张从SP是短暂的,可能是由于tachyphylaxis.
研究的目的:
- 研究静脉注射物质P对全身和冠状动脉循环的平稳状态影响.
- 为了确定SP对有意识,有仪器的狗的影响.
主要方法:
- 静脉注射物质P (5 ng/kg/min) 给有意识的,自主反射完整的狗.
- 利用节阻塞来评估自主影响.
- 进行了物质P (0.4 ng/kg/min) 的冠心内输液,用于直接冠心作用.
主要成果:
- 静脉注射SP增加了心脏输出量和心率,同时降低了平均动脉压和总周围阻力.
- 脊髓炎导致冠状动脉血管收缩,减少冠状动脉血流和心肌氧气供应.
- 关节性阻塞加剧了SP诱导的冠状动脉血管收缩.
- 内冠状动脉SP直接导致持续的冠状动脉血管收缩.
结论:
- 在有意识的狗中,物质P主要导致全身血管扩张.
- 矛盾的是,物质P会引起冠状动脉血管收缩,减少心肌的氧气供应.
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