Which neurotransmitter effect does atropine primarily target?

Atropine primarily targets the neurotransmitter acetylcholine. This drug is an antagonist to the muscarinic acetylcholine receptors, which are found throughout the body, especially in the parasympathetic nervous system. By blocking these receptors, atropine inhibits the actions of acetylcholine, leading to effects such as increased heart rate, reduced saliva production, and decreased gastrointestinal motility.

The action of atropine is particularly important in clinical settings where it is used to treat bradycardia (slow heart rate) and to decrease secretions prior to surgery. Its selectivity for acetylcholine and its impact on the parasympathetic nervous system make it a key pharmacologic agent in situations requiring a decrease in acetylcholine's effects.