# Acetylcholine --- **Acetylcholine** or **ACh** is a [[neurotransmitter]] which plays multiple roles such as: - motor function - [[autonomic nervous system]] (both sympathetic and parasympathetic) - sleep and arousal - pain perception - memory - leaning, specifically focused learning (paying close attention) - leads to new long-term memory formation. **Acetylcholinesterase** is an enzyme that lives in synapses that cleaves ACh into acetate and choline, which are then reabsorbed by the neuron and moved by [[neurons|retrograde transport]] to the soma, where they are recombined into ACh. [[Anticholinergics]] are a class of medication that reduce ACh activity. ## Cholinergic Receptors **Cholinergic receptors** are any receptor that receives acetylcholine as a neurotransmitter. There are two types of cholinergic receptors, **muscarinic** and **nicotinic** receptors. ## Imbalances with Acetylcholine - increased levels of acetylcholine can contribute to: - [[depression]] - decreased levels of acetylcholine can contribute to: - [[Alzheimer's disease]] - [[Huntington's disease]] - [[Parkinson's disease]] - [[myasthenia gravis]] is a condition which destroys the acetylcholine receptors on muscle cells, effectively blocking it's usage ___