This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.N.S, Subject name: Pharmacology
Buprenorphine is partial agonist of 
Select and explain. 
A. Mu (u) receptor, B. Delta (d) receptor, C. Kappa (k) receptor, D. Sigma (s) receptor
A: Mu (u) receptor
Answer: A: Mu (u) receptor 
Explanation: Ans. is 'a' i.e., Mu (m) receptor BuprenorphineReceptor p(mu) - Partial agonistK (kappa) - Antagonist (moderate) d (delta) - Also know -Buprenorphine produces ceiling effect