Review Article

Measuring synaptic vesicles using cellular electrochemistry and nanoscale molecular imaging

  • Nature Reviews Chemistry 1, Article number: 0048 (2017)
  • doi:10.1038/s41570-017-0048
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Abstract

The synaptic vesicle, a cellular compartment tens to hundreds of nanometres in size, is a main player in the process of exocytosis for neuronal communication. Understanding the regulatory mechanism of neurotransmission and neurological disorders requires the quantification of chemicals transmitted between cells. These challenging single vesicle measurements can be performed using analytical techniques described in this Review. In vivo amperometry at living cells can be used to quantify the amount of neurotransmitter released from a vesicle. By contrast, intracellular vesicle impact electrochemical cytometry allows the amount of molecules to be determined inside single vesicles. Although the dominant mode of exocytosis from vesicles is still under debate, several experiments point to the importance of partial release modes. Making use of fluorescent or isotopically labelled probes enables super-resolution optical and mass spectrometric imaging of molecular composition and activity of single vesicles. Correlating results from these nanoscopic techniques with those from electrochemistry has proved advantageous in understanding the relationship between vesicle structure and function.

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Acknowledgements

The authors thank S. O. Rizzoli for helpful comments, and the many colleagues and collaborators that have contributed to work cited in this Review. This work was supported by the Knut and Alice Wallenberg Foundation, the Swedish Research Council, the European Research Council, and the US National Institutes of Health.

Author information

Affiliations

  1. University of Gothenburg, Department of Chemistry and Molecular Biology, Gothenburg 41296, Sweden.

    • Nhu T. N. Phan
    • , Xianchan Li
    •  & Andrew G. Ewing
  2. University of Göttingen Medical Center, Institute of Neuro- and Sensory Physiology, Göttingen 37073, Germany.

    • Nhu T. N. Phan
  3. Chalmers University of Technology, Department of Chemistry and Chemical Engineering, Gothenburg 41296, Sweden.

    • Andrew G. Ewing

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Competing interests

The authors declare no competing interests.

Corresponding author

Correspondence to Andrew G. Ewing.