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Related to muscarinic receptors: cholinergic receptors
membrane-bound proteins with an extracellular domain that contains a recognition site for acetylcholine (ACh); combination of Ach with the receptor initiates a physiologic change (slowing of heart rate, increased glandular secretory activity, and stimulation of smooth muscle contractions); changes are observed after treatment with the mushroom alkaloid muscarine. Muscarinic receptors are to be distinguished from nicotinic receptors.
pertaining to the transmission of nerve impulses mediated by muscarinic receptors; these may be adrenergic or cholinergic.
includes slowing and reduced stroke volume of the heart, bronchiolar constriction, arteriolar dilatation, increased tone, motility and secretion in the alimentary tract, and increases in salivation and lacrimation.
muscarinic blocking agents
block muscarinic receptors, e.g. atropine and the synthetic agents homatropine, methantheline, propantheline and methylatropine.
cholinergic receptors of autonomic effector cells (and also on some autonomic ganglion cells and some central neurons) that are stimulated by muscarine and parasympathomimetic drugs and antagonized by atropine.