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What is GPCR that does not act through opening of potassium channels is? and explain in detail?
Ans. D. Angiotensin 1 receptor* Four G protein gated inwardly-rectifying potassium (GIRK) channel subunits have been identified in mammals: GIRK1, GIRK2, GIRK3, and GIRK4. The GIRK subunits come together to form GIRK ion channels.* Activation of the IKACh channels begins with release of acetylcholine (ACh) from the vagus nerve onto pacemaker cells in the hea.* ACh binds to the M2 muscarinic acetylcholine receptors, which interact with G proteins.