在麻醉大鼠急性心肌缺血前5 min iv内皮素-1 1.5—3.0μg·kg~(-1)导致室颤阈呈剂量和时间依赖性降低,其作用持续至少60min。当内皮素-1剂量在3.0μg·kg~(-1)时,自发性室速显著增加,心肌梗死范围明显扩大,动脉血压处于较高水平。钙拮抗剂地尔硫(艹卓)能部分地预防内皮素-1引起的室颤阈下降,完全对抗其加压反应且有效限制心肌坏死的扩展。 Endothelin-1 1.5-3.0 μg · kg -1 5 min before the acute myocardial ischemia in anesthetized rats resulted in a dose-and time-dependent reduction of the ventricular fibrillation threshold for at least 60 min. When the concentration of endothelin - 1 was 3.0μg · kg ~ (-1), the spontaneous ventricular tachycardia increased significantly, the range of myocardial infarction was obviously enlarged, and the arterial pressure was at a high level. Diltiazem, a calcium antagonist, partially prevented endothelin-1-induced decrease in ventricular fibrillation threshold, completely antagonizing its pressure response and effectively limiting the expansion of myocardial necrosis.