Wichmann J, Ertl G, Höhne W, Schweisfurth H, Wernze H, Kochsiek K
Am J Cardiol. 1983 Oct 1;52(7):887-92. doi: 10.1016/0002-9149(83)90435-6.
The effects of atrial fibrillation (AF) on coronary circulation before and after alpha-receptor blockade were studied in 14 anesthetized, open-chest dogs. AF was induced by electrical stimulation of the left atrial appendage; identical rhythmic heart rates were adjusted by left atrial pacing. During atrial pacing, coronary vascular resistance (CVR) was 0.97 +/- 0.10 mm Hg X min X 100 g/ml (resistance units [RU]), coronary blood flow (CBF) 125 +/- 14 ml/min X 100 g, and oxygen saturation 30 +/- 2%; plasma epinephrine was 193 +/- 42 pg/ml and norepinephrine 584 +/- 111 pg/ml. During AF, CVR was higher (1.16 +/- 0.11 RU, p less than 0.0005), whereas CBF (92 +/- 9 ml/min X 100 g, p less than 0.001) and coronary sinus oxygen saturation (24 +/- 2%, p less than 0.0025) were lower than during atrial pacing. When AF was induced, epinephrine increased to 333 +/- 98 pg/ml (p less than 0.05) and norepinephrine to 1,005 +/- 214 pg/ml (p less than 0.005). The large increase in plasma catecholamines suggested an activation of the sympathoadrenal system during AF. In addition, the alpha-receptor blocker phenoxybenzamine (10 mg/kg, intravenously) abolished the differences in CVR, CBF and oxygen saturation between AF and atrial pacing. The data suggest that the decrease in CBF and increase in CVR during experimentally induced AF are caused by coronary vasoconstriction, mediated by sympathetic activation of alpha receptors in the coronary vascular bed.
在14只麻醉开胸犬身上研究了心房颤动（AF）对α受体阻断前后冠状动脉循环的影响。通过电刺激左心耳诱发房颤；通过左心房起搏调整为相同的节律性心率。在心房起搏期间，冠状动脉血管阻力（CVR）为0.97±0.10 mmHg×min×100 g/ml（阻力单位[RU]），冠状动脉血流量（CBF）为125±14 ml/min×100 g，氧饱和度为30±2%；血浆肾上腺素为193±42 pg/ml，去甲肾上腺素为584±111 pg/ml。在房颤期间，CVR较高（1.16±0.11 RU，p<0.0005），而CBF（92±9 ml/min×100 g，p<0.001）和冠状窦氧饱和度（24±2%，p<0.0025）低于心房起搏期间。诱发房颤时，肾上腺素增加至333±98 pg/ml（p<0.05），去甲肾上腺素增加至1005±214 pg/ml（p<0.005）。血浆儿茶酚胺的大幅增加表明房颤期间交感肾上腺系统被激活。此外，α受体阻滞剂酚苄明（10 mg/kg，静脉注射）消除了房颤和心房起搏之间CVR、CBF和氧饱和度的差异。数据表明，实验诱发房颤期间CBF的减少和CVR的增加是由冠状动脉血管收缩引起的，这是由冠状动脉血管床中α受体的交感神经激活介导的。
