[Mechanism of coronary vasodilation in myocardial regional hypoxia].
OBJECTIVE
To determine if coronary vasodilation is dependent upon adrenergic activation during myocardial regional.


METHODS
Studies were conducted in 10 Mongrel dogs of either sexes, in which LAD was perfused with normoxic (CAO2 = 18.4-20.4 ml/100 ml) or regional hypoxic (CAO2 = 7.8-8.1 ml/100 ml) blood with coronary perfusion system by self-control methods.


RESULTS
No significant differences were observed in hemodynamic values with regional hypoxia compared with normoxia before adrenergic receptor blocker was given, but coronary blood flow increased by 225%. There were significant differences in dp/dt max, dp/dt min after adrenergic blocker was given. Whether there was regional hypoxia or not, coronary blood flow still increased by 190%.


CONCLUSIONS
Coronary vasodilation is independent upon adrenergic activation during myocardial regional hypoxia.
Department of Circulation, First Clinical College, China Medical University, Shenyang.
X
X
Bai
J
J
Wang
Y
Y
Li
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D003331:Coronary Vessels / Q000503:physiopathology*; D004285:Dogs; D005260:Female; D008297:Male; D017202:Myocardial Ischemia / Q000503:physiopathology*; D014664:Vasodilation
D000319:Adrenergic beta-Antagonists