Exocytosis determination of SH-SY5Y single cell stimulated by diff erent stimulants on indium tin oxide (ITO) micro-pore electrode

The human neuroblastoma SH-SY5Y cell line has been used as a model to study mechanisms of neurotransmitter release.In order to study the mechanism of SH-SY5Y single cell exocytosis stimulated by different stimulants,including high K+,3-(1-nitroso-2-pyrrolidinyl)pyridine and nicotine,a type of indium tin oxide(ITO)micro-pore electrode was used to obtain the corresponding amperometric response time.When the cell is stimulated by 0.1 M K+,almost immediate exocytosis could be detected,due to the rapid depolarization of cell membrane.However,the stimulations with 1 mM nicotine and 3-(1-nitroso-2-pyrrolidinyl)pyridine result in a short delay between stimulation and exocytosis,which can be correlated with the time needed for binding of the stimulant to the nicotinic acetylcholine(ACh)receptor and the induction of post-binding phenomena.Thus,the response time of SH-SY5Y single cell exocytosis is significantly affected by the exocytosis mechanisms.