This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: AIIMS 2019, Subject name: Pharmacology
G-protein coupled receptor that does not act through opening of potassium channels is 
Select and explain. 
A. Muscarinic M2 receptor, B. Dopamine D2 receptor, C. Serotonin 5 HT 1 receptor, D. Angiotensin 1 receptor
D: Angiotensin 1 receptor
Answer: D: Angiotensin 1 receptor 
Explanation: * DGPCR which act through opening of K+ channels lead to hyper polarisation, thus leading to inhibition.So, receptor which causes stimulation will not act through opening of K+ channels. o Muscarinic M2 receptor, Dopamine D2 receptor and serotonin 5HT1 receptor act through opening of K+ channels.o Whereas Angiotensin 1 receptor act by increasing Ca+2.