muscarinic receptor
Quick Summary
Muscarinic receptors are a type of acetylcholine receptor found in the nervous system. Unlike nicotinic receptors, which directly open ion channels, muscarinic receptors are membrane proteins that indirectly open ion channels through a second messenger system. This indirect mechanism results in a relatively slower action compared to nicotinic receptors. Muscarinic receptors are more prevalent in higher levels of the central nervous system. Drugs like pilocarpine act as agonists at muscarinic receptors, used to constrict pupils and reduce eye pressure in glaucoma. Antagonists such as atropine and scopolamine block muscarinic receptors, suppressing parasympathetic nervous system actions like secretions and smooth muscle contraction.12
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nervous systemAcetylcholineThe muscarinic receptor, on the other hand, is a membrane protein; upon stimulation by neurotransmitter, it causes the opening of ion channels indirectly, through a second messenger. For this reason, the action of a muscarinic synapse is relatively slow. Muscarinic receptors predominate at higher levels of…
Read MoreThe muscarinic receptor, on the other hand, is a membrane protein; upon stimulation by neurotransmitter, it causes the opening of ion channels indirectly, through a second messenger. For this reason, the action of a muscarinic synapse is relatively slow. Muscarinic receptors predominate at higher levels of…
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human nervous systemNeurotransmitters and receptorsMuscarinic receptors are associated mainly with parasympathetic functions and are located in peripheral tissues (e.g., glands and smooth muscle). Peptidergic receptors exist in target cells as well.
Read MoreMuscarinic receptors are associated mainly with parasympathetic functions and are located in peripheral tissues (e.g., glands and smooth muscle). Peptidergic receptors exist in target cells as well.
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