On the regulation of acetylcholine release: a study utilizing Torpedo synaptosomes and synaptic vesicles.
1. Addition of ATP to isolated highly purified Torpedo synaptic vesicles results in 45Ca2+ uptake. 2. Ca2+ dependent ACh release from Torpedo synaptosomes is accompanied by the phosphorylation of a specific protein with an apparent subunit molecular weight of about 100,000 (band alpha). 3. Activation of the presynaptic muscarinic receptors by an agonist inhibits Ca2+-dependent ACh release from Torpedo synaptosomes. This process seems to be mediated through an interference with the phosphorylation of the band alpha protein, and not by blocking the voltage-dependent presynaptic Ca2+ channel.
D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000378:metabolism; D005399:Fishes / Q000378:metabolism*; D066298:In Vitro Techniques; D010277:Parasympathomimetics / Q000494:pharmacology; D010766:Phosphorylation; D013572:Synaptic Vesicles / Q000378:metabolism*; D013574:Synaptosomes / Q000378:metabolism*
D010277:Parasympathomimetics; D000109:Acetylcholine; D002118:Calcium