Experimental study on role of endogenous endothelin in echocardiographic evaluation of flow-dependent epicardial coronary vasodilation induced by reactive hyperemia after blockade of nitric oxide formation / 中华超声影像学杂志

ABSTRACT

Objective To determine whether endogenous endothelin(ET) plays a role in the echocardiographic evaluation of the flow-dependent epicardial coronary vasodilation induced by reactive hyperemia(RH) after blockade of nitric oxide(NO) formation. Methods In six anesthetized open-chest dogs, changes in internal diameter of the left anterior descending coronary artery(LAD) induced by RH were investigated via echocardiography before intracoronary infusion of GN-nitro-L-arginine methyl ester(L-NAME), after blockade of NO formation by L-NAME, and after L-NAME plus intracoronary infusion of BQ-123, an ETA receptor blocker.Results Before intracoronary infusion of L-NAME, the diameter of LAD increased significantly from((2.24)?(0.21))mm to ((2.51)?(0.23))mm (P