#structural action
- Atropine — A toxic alkaloid extracted from deadly nightshade (Atropa belladonna) and other plants of the Solanaceae family, used in medicine as a parasympatholytic agent; it acts structurally by blocking acetylcholine muscarinic receptors, causing effects such as pupil dilation (mydriasis), reduction of glandular secretions, and acceleration of the heart rate. It represents an essential antidote in poisonings with organophosphorus pesticides or nerve gases.