This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous (Pharmacology), Subject name: Pharmacology
[{'content': 'Which does not act as 2nd messenger? \nSelect and explain. \nA. cAMP, B. Guanyl cyclase, C. Diacyl glycerol, D. Inositol triphosphate', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B. Guanyl cyclase2nd messengers are responsible for conducting and amplifying signals of GPCRs. Following substance act as 2nd messengers:a. cAMP or cGMP causes protein phosphorylationb. IP3- calcium release from ERc. DAG - activates enzymes such as protein kinase C', 'role': 'assistant'}]