Role of endothelin in a rabbit model of acute myocardial infarction: effects of receptor antagonists
Abstract
The role of endothelin (ET) in acute myocardial infarction and proarrhythmic potential was investigated in a rabbit model. One group of rabbits underwent 30 min of circumflex occlusion and 3 h of reperfusion with measurements of myocardial blood flow and myocardial levels of ET-1 messenger RNA (mRNA). In a second group, the systemic and coronary effects of exogenous ET were studied in animals pretreated with either saline, FR139317, an ETA-receptor antagonist, or PD145065, an ETA-and ETB-receptor antagonist. In a third study, animals undergoing 30 min of circumflex occlusion followed by 48 h of reperfusion were treated with exogenous ET-1, FR139317, PD145065, or saline. Arrhythmias were recorded and infarct size measured at 48 h. These studies revealed that ischemia and reperfusion was followed by a progressive microcirculatory failure ("no-reflow phenomenon") in rabbits. This was associated with a 2.6-fold elevation in levels of myocardial ET-1 mRNA in the ischemic zone in comparison to the nonischemic zone (p = 0.04). Exogenous ET-1 caused elevation in coronary and systemic vascular resistance that was significantly blocked by antagonism of the ETA receptor. In rabbits subjected to myocardial ischemia and reperfusion, ET-1 in...Continue Reading
References
Endothelin 1 mediates ex vivo coronary vasoconstriction caused by exogenous and endogenous cytokines
Citations
Related Concepts
Related Feeds
Atrial Fibrillation
Atrial fibrillation is a common arrhythmia that is associated with substantial morbidity and mortality, particularly due to stroke and thromboembolism. Here is the latest research.
Arrhythmia
Arrhythmias are abnormalities in heart rhythms, which can be either too fast or too slow. They can result from abnormalities of the initiation of an impulse or impulse conduction or a combination of both. Here is the latest research on arrhythmias.
CZI Human Cell Atlas Seed Network
The aim of the Human Cell Atlas (HCA) is to build reference maps of all human cells in order to enhance our understanding of health and disease. The Seed Networks for the HCA project aims to bring together collaborators with different areas of expertise in order to facilitate the development of the HCA. Find the latest research from members of the HCA Seed Networks here.