On the regulation of acetylcholine release: a study utilizing Torpedo synaptosomes and synaptic vesicles
Michaelson, D.M.; Avissar, S.; Ophir, I.; Pinchasi, I.; Angel, I.; Kloog, Y.; Sokolovsky, M.
Journal de Physiologie 76(5): 505-514
1980
ISSN/ISBN: 0021-7948 PMID: 7452519 Document Number: 155809
Addition of ATP to isolated highly purified Torpedo synaptic vesicles resulted in 45Ca2+ uptake. Ca2+ dependent ACh acetylcholine release from Torpedo synaptosomes was accompanied by the phosphorylation of a specific protein, with an apparent subunit MW of about 100,000 (band .alpha.). Activation of the presynaptic muscarinic receptors by an agonist inhibited Ca2+-dependent ACh release from Torpedo synaptosomes. This process seems mediated through an interference with the phosphorylation of the band .alpha. protein, and not by blocking the voltage-dependent presynaptic Ca2+ channel.