Tracer Flux Measurements to Study Outward Transport by Monoamine Neurotransmitter Transporters

  • Thomas Steinkellner
  • Felix P. Mayer
  • Tina Hofmaier
  • Marion Holy
  • Therese Montgomery
  • Birgit Eisenrauch
  • Michael Freissmuth
  • Harald H. SitteEmail author
Part of the Neuromethods book series (NM, volume 118)


The physiological role of neurotransmitter transporter (NTT) proteins is the reuptake of released neurotransmitter from the synaptic cleft. NTTs accomplish uptake by undergoing a transport cycle, which relies on a return step in the empty state. In addition, NTTs can also run in the reverse direction and transport substrates out of the cells. This can be observed under conditions, where the transmembrane sodium gradient dissipates, e.g., if sodium accumulates within the cell. This reverse transport mode is also induced by amphetamines and the exact mechanism underlying the amphetamine action is still enigmatic and involves complex regulatory processes. In the current chapter, we describe various methods that can be used to assess the efflux of neurotransmitter from cells heterologously expressing the NTTs of interest or from preparations derived from intact brain tissue.

Key words

Carrier-mediated efflux Transport reversal Neurotransmitter transporter Superfusion Radiolabeled tracer flux Heterologous cell expression systems Synaptosomes Brain slices 



The authors wish to thank the Austrian Science Fund for continuous support (grant F35).


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Thomas Steinkellner
    • 1
  • Felix P. Mayer
    • 1
  • Tina Hofmaier
    • 1
  • Marion Holy
    • 1
  • Therese Montgomery
    • 1
    • 2
  • Birgit Eisenrauch
    • 1
  • Michael Freissmuth
    • 1
  • Harald H. Sitte
    • 1
    Email author
  1. 1.Center of Physiology and Pharmacology, Institute of PharmacologyMedical University of ViennaViennaAustria
  2. 2.School of Biomolecular and Biomedical ScienceUniversity College DublinDublinIreland

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