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Pharmaceutisch Weekblad

, Volume 6, Issue 6, pp 241–244 | Cite as

Does the tissue concentration in receptor binding studies change the affinity of the labelled ligand?

  • K. Ensing
  • R. A. De Zeeuw
Short Communications

Abstract

When the tissue concentration in a radioreceptor assay for anticholinergic drugs was varied in order to obtain optimum conditions, and the receptor concentration Ct and the equilibrium dissociation constant KD were determined by Scatchard analysis, the KD increased with increasing tissue concentrations. This phenomenon was considered as an artefact caused by non-specific binding of the labelled ligand to constituents of the receptor preparation which were not completely retained on the glassfibre filters used for the separation of bound and free fraction of radio-labelled ligand. The increase in KD in these experiments could be described with a mathematical model of the binding experiments.

Keywords

Receptor Binding Tissue Concentration Binding Study Binding Experiment Free Fraction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Royal Dutch Association for Advancement of Pharmacy 1984

Authors and Affiliations

  • K. Ensing
    • 1
  • R. A. De Zeeuw
    • 1
  1. 1.Department of ToxicologyState University of GroningenAW GroningenThe Netherlands

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