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Updated: Jul 24, 2026

Subcutaneous Administration of Muscarinic Antagonists and Triple-Immunostaining of the Levator Auris Longus Muscle in Mice
Published on: September 8, 2011
Calcium antagonism of anionic liposome actions at a muscarinic synapse
Abstract:
Addition of 0.5 mM Ca++ to guinea pig ileum longitudinal muscle-myenteric plexus preparation, which is contracted under the influence of anionic liposomes, is followed by a rapid, temporary, relaxation. Such Ca++ addition produces no change in the field-stimulated preparation, eliminating direct Ca++ effects or neuronal acetylcholine release nor in the preparation stimulated by added acetylcholine, eliminating direct Ca++ effects on muscle. These eliminations leave the Ca++ interaction with liposomes, probably causing self-fusion, and loss from interaction with cholinergic neurons, as the mechanism for Ca++-induced relaxation.
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