Abstract
Magnolol, an antioxidant, has been reported to possess various protective effects
on the cardiovascular system. However, its effect on myocardial stunning has not been
elucidated. The purpose of this study was to investigate the anti-stunning effect
of magnolol by evaluating the recovery of regional myocardial function after 10-minute
coronary artery occlusion in anesthetized, open-chest rabbits. There was no significant
hemodynamic change after intravenous infusion of magnolol. Systolic wall thickening
fraction (WThF) measured with an epicardial Doppler sensor in animals pretreated with
normal saline and vehicle solution remained significantly depressed (60 ± 7 % and
77 ± 4 % of baseline WThF, respectively) 3 hours after coronary artery reperfusion
(CAR). Pretreatment with magnolol (10-7 and 10-6 g/kg, intravenous infusion) significantly enhanced the recovery of systolic wall
thickening fraction (98 ± 1 and 99 ± 1 % of baseline WThF, respectively) 60 minutes
after CAR. This study demonstrated that intravenous pretreatment with magnolol protected
myocardium against stunning.
Key words
Magnolol - myocardial stunning - myocardial protection - coronary artery occlusion
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Ph.D. MD Prof. Shen-Kou Tsai
College of Medicine National Taiwan University National Taiwan University Hospital
Chairman, Department of Anesthesiology Professor of Anesthesiology
7, Chung-Shan South Road
Taipei
Taiwan, 100-16, R.O.C.
Email: sktsai@ha.mc.ntu.edu.tw
Phone: 011-886-2-23415736
Fax: 011-886-2-23562157