Exocytosis of SH-SY5Y single cell with different shapes cultured on ITO micro-pore electrode.

Communication between cells by release of specific chemical messengers via exocytosis plays crucial roles in biological process. Catecholamines, like dopamine, epinephrine, and norepinephrine, which are types of neurotransmitters released from cells, can be oxidized and detected by the microelectrodes, and amperometric detection of exocytosis is an effective method for studying the communication between cells. The experimental results depend on many factors, among which the property of the microelectrode, cell states, and their positions to each other are particularly important. A type of indium tin oxide (ITO) micro-pore electrodes, which is characterized by its stability, has been developed with photolithography. SH-SY5Y cells can adhere and spread on ITO micro-pore electrodes. Therefore, it is possible to investigate the correlation between cell morphology and exocytosis. The results show that cells with clear process have higher release frequency of norepinephrine compared with cells in spherical shape. Combined with fluorescence observation, this technique provides a simple and convenient methodology for cell study.