Nicotinic acetylcholine receptors
Nicotinic Acetylcholine Receptors
Nicotinic acetylcholine receptors (nAChRs; pronounced as "nick-oh-tin-ic a-seh-til-coh-leen ree-sep-tors") are a type of protein that responds to the neurotransmitter acetylcholine. nAChRs are found in many tissues in the body and play a role in muscle contraction, heart rate, memory, and other functions.
Etymology
The term "nicotinic" is derived from nicotine, the addictive substance in tobacco that binds to nAChRs, while "acetylcholine" refers to the neurotransmitter that normally activates these receptors.
Structure and Function
nAChRs are made up of five subunits that form a central pore. When acetylcholine or other agonists bind to the receptor, the pore opens to allow ions to flow across the cell membrane. This ion flow changes the electrical charge inside the cell, leading to various cellular responses.
Types of nAChRs
There are several types of nAChRs, including muscle-type receptors found at the neuromuscular junction, and neuronal-type receptors found in the central and peripheral nervous systems. Each type of receptor has a different combination of subunits, which affects its response to acetylcholine and other drugs.
Clinical Significance
nAChRs are involved in several diseases, including myasthenia gravis, a condition that causes muscle weakness, and Alzheimer's disease, which is associated with a loss of cholinergic neurons in the brain. Drugs that target nAChRs, such as nicotine and certain medications for Alzheimer's disease, can have therapeutic effects.
Related Terms
This WikiMD.org article is a stub. You can help make it a full article.