Dopamine release from nerve endings induced by polysialogangliosides

Polysialogangliosides but not monosialoganlioside or a neutral glycosphingolipid induce release of ³H] -dopamine from synaptosomes in presence of Ca⁺⁺, presumably by exocytosis. This effect is discussed in relation to the ability of polysialogangliosides to induce membrane fusion in chicken erythrocytes and to their behaviour in lipid monolayers. It is suggested that characteristic interactions with phosphatidylcholine involving decreases of surface potential are participating in the polysialoganglioside-induced neurotransmitter release.