This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cardiovascular system, Subject name: Pharmacology
[{'content': 'Most potent cardiac stimulant among the following is? \nSelect and explain. \nA. Adrenaline, B. Noradrenaline, C. Ephedrine, D. Salbutamol', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Epinephrine (adrenaline) is an agonist at both a and b receptors. It is, therefore, a very potent vasoconstrictor and cardiac stimulant. Noradrenaline acts mainly on alpha receptors salbutamol acts on beta 2 receptors beta 1 receptors are located on hea Katzung 12e pg:140', 'role': 'assistant'}]