Which of the Following is Least True of the Vagus

Question

Which of the following is least true of the vagus nerve?
A) Cholinergic
B) Slows heart rate
C) Effect on the heart is eliminated by a beta1-adrenergic blocker
D) Transmitter is ACh

Accepted Answer

This statement is the least true because beta1-adrenergic blockers (such as propranolol) do not eliminate the effect of the vagus nerve on the heart, as the vagus nerve operates through the parasympathetic nervous system and not the sympathetic nervous system which is targeted by beta1 blockers. The other statements are true of the vagus nerve: it is cholinergic, slows heart rate, and releases acetylcholine as its neurotransmitter.