This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Acute coronary syndrome, Subject name: Medicine
[{'content': 'Which amongst the following endothelin is involved in MI? \nSelect and explain. \nA. Endothelin 1, B. Endothelin 2, C. Endothelin 3, D. Endothelin 4', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Plasma ET-1 levels are raised after acute myocardial infarction due to coronary vasoconstriction-Myocardial ischemia -Ventricular dysfunction. Endothelin (ET)-1 is a potent coronary vasoconstrictor.', 'role': 'assistant'}]