- Atropine is a parasympatholytic drug, it inhibits the effect of Acetyl choline on muscarinic receptors.
- Nicotine is a ganglion blocker, it inhibits the transmission of impulse through autonomic ganglia.
Q1. Name the cholinergic receptors and their antagonists.
Muscarinic cholinergic receptors
- Actions of ACh on cardiac muscle (inhibition), smooth muscle, and exocrine glands, including sweat glands
- Blocked by atropine
Nicotinic cholinergic receptors
- Actions of ACh on motor end-plates
- Blocked by curare
- Actions of ACh on postganglionic neurons in autonomic ganglia
- Blocked by hexamethonium
Q2. What is the effect of atropine on the heart?
- Atropine is a cholinergic muscarinic blocker. It prevents the action of acetylcholine on the heart muscles hence increasing the activity of the heart muscle.