Acetylcholine acts on m<sub>2</sub>‐muscarinic receptors to excite rat locus coeruleus neurones
British Journal of PharmacologyPublished 1 August 1985Open access
Terrance M. Egan, R. Alan North
Citations264
SJR quartileQ1
SJR score2.34
SNIP1.51
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TL;DR
In hexamethonium, pirenzepine shifted the acetylcholine dose‐response curve to the right with an equilibrium dissociation constant of 200 nM, indicating an interaction with a m2‐type of muscarinic receptor.
Abstract
Intracellular recordings were made from neurones of the rat locus coeruleus in vitro. Acetylcholine increased the firing rate by depolarizing the membrane; both muscarinic and nicotinic antagonists partially reduced this effect. In hexamethonium, pirenzepine shifted the acetylcholine dose-response curve to the right with an equilibrium dissociation constant of 200 nM, indicating an interaction with a m2-type of muscarinic receptor.
Keywords
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