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: Physiology
[{'content': 'Antiemetic action is through ? \nSelect and explain. \nA. Chemoreceptor triggrezone (CTZ), B. H1 agonist, C. Diantagonist, D. Olfactory apparatus', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., .LCTZThe chemoreceptor trigger zone (CTZ) - most impoant.The vestibular systemThe periphery, e.g. distension or irritation of the gut, myocardial infarction, biliary or renal stone.Coical centresVomiting centre and nucleus of tractus solitarius contain muscarinic cholinergic and histamine H1 receptors.CTZ is located in area postrema (outside BBB) and contains Dopamine D2, opioid & serotonine 5-HT3 receptors.So, antiemetic that act on vomiting centre have antimuscarinic and antihistaminic action can allete vomiting from any cause.", 'role': 'assistant'}]