Muscarinic receptors on blood vessel endothelium cause
Ans. is'b' i.e., Vasodilatation through NONo direct cholinergic supply is present in blood vessels.But cholinergic receptor (M, types) are present on blood vessels endothelium.Stimulation of these receptors causes release of EDRF (NO) from endothelium resulting in vasodilatation.
Vasodilatation through acetylcholine
Vasodilatation through NO
Vasoconstriction through acetylcholine
Vasoconstriction through endotheline