VMAT-Mediated changes in quantal size and vesicular volume

T. L. Colliver, S. J. Pyott, M. Achalabun, Andrew G. Ewing

Research output: Contribution to journalArticleAcademicpeer-review

179 Citations (Scopus)


It has been well established that the volume of secretory vesicles can be modulated. However, we present the first data demonstrating that the amount of transmitter in a vesicle can regulate its volume. Amperometry and transmission electron microscopy have been used to determine that l-3,4-dihydroxyphenylalanine and reserpine increase and decrease, respectively, the volume of single pheochromocytoma cell vesicles as well as their catecholamine content. Because changes in vesicular catecholamine content are tracked by changes in vesicle volume, our results indicate that when quantal size is altered via the vesicular monoamine transporter the concentration of catecholamines within the vesicles remains relatively constant. This previously unidentified cellular response provides new insight into how catecholamines can be packaged in and released from secretory vesicles.

Original languageEnglish
Pages (from-to)5276-5282
Number of pages7
JournalThe Journal of Neuroscience
Issue number14
Publication statusPublished - 15-Jul-2000
Externally publishedYes


  • Action Potentials
  • Adrenergic Uptake Inhibitors
  • Animals
  • Catecholamines
  • Cell Size
  • Dihydroxyphenylalanine
  • Dopamine Agents
  • Electrochemistry
  • Membrane Glycoproteins
  • Membrane Transport Proteins
  • Microscopy, Electron
  • Neuropeptides
  • Organelles
  • PC12 Cells
  • Rats
  • Reserpine
  • Vesicular Biogenic Amine Transport Proteins
  • Vesicular Monoamine Transport Proteins

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