Amperometry is widely used to study exocytosis of neurotransmitters and hormones in various cell types. Analysis of the shape of the amperometric spikes that originate from the oxidation of monoamine molecules released during the fusion of individual secretory vesicles provides information about molecular steps involved in stimulation-dependent transmitter release. Here we present an overview of the methodology of amperometric signal processing, including (i) amperometric signal acquisition and filtering, (ii) detection of exocytotic events and determining spike shape characteristics, and (iii) data manipulation and statistical analysis. The purpose of this review is to provide practical guidelines for performing amperometric recordings of exocytotic activity and interpreting the results based on shape characteristics of individual release events.
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We thank M. Lindau, R. Staal and Y. Schmitz for critique of the manuscript and J.B. Sørensen, R. Borges and other participants of 12th International Symposium on Chromaffin Cell Biology for helpful discussion. Supported by Parkinson's Disease Foundation, Picower Foundation and National Institute of Drug Abuse grant 07418.
The authors declare no competing financial interests.
Finding spike beginning and end. (PDF 106 kb)
Statistical analysis of different foot subpopulations. (PDF 160 kb)
Analysis of overlapping spikes. (PDF 148 kb)
Statistical analysis of different spike subpopulations. (PDF 192 kb)
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Mosharov, E., Sulzer, D. Analysis of exocytotic events recorded by amperometry. Nat Methods 2, 651–658 (2005) doi:10.1038/nmeth782
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