This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
[{'content': 'Which of the following actions is not caused by H1 receptor - \nSelect and explain. \nA. Vasocontriction, B. Gastric acid secretion, C. | Permeability, D. Bronchoconstriction', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Gastric acid secretion Gastric secretion is H2mediated.", 'role': 'assistant'}]