Psychopharmacology

, Volume 89, Issue 4, pp 436–439

High affinity binding of3H-paroxetine and3H-imipramine to rat neuronal membranes

  • Erling T. Mellerup
  • Per Plenge
Original Investigations

Abstract

Paroxetine is the most potent and one of the most specific serotonin uptake inhibitors. High-affinity3H-paroxetine and3H-imipramine binding was compared in rat neuronal membranes.

TheKd value for3H-paroxetine binding to neuronal membranes was 0.08 nM, which is exactly the same value as with platelet membranes. TheKd value for3H-imipramine binding to neuronal membranes was about 4 nM, which is higher than theKd value for3H-imipramine binding to platelet membranes (0.5 nM).

The results indicated that the3H-paroxetine binding site is identical in neuronal membranes and in platelet membranes; this binding site is probably located on the serotonin transport mechanism. In addition, part of the highaffinity3H-imipramine binding to neuronal membranes is probably located on the serotonin transport mechanism, but another part is located elsewhere. Furthermore the polypeptides containing the3H-imipramine binding sites may not be identical in neuronal and platelet membranes.

Key words

3H-paroxetine 3H-imipramine Binding sites Rat neuronal membranes 

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Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • Erling T. Mellerup
    • 1
  • Per Plenge
    • 1
  1. 1.Psychochemistry InstituteUniversity of CopenhagenCopenhagenDenmark

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