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': 'Which of the following drug reduces blood pressure by directly decreasing the hea rate: \nSelect and explain. \nA. Propanolol, B. Prazosin, C. Alpha methyl dopa, D. Nitroprusside sodium', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Propranolol is a non-selective beta blocker. It has a negative chronotropic effect (decreases hea rate) It decreases hea rate by blocking the beta1 receptors located on the hea. It also decreases renin production from JG cells of kidney decreasing BP (Ref- Essentials of medical pharmacology K D TRIPATHI 8th Edition)', 'role': 'assistant'}]