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

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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.

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Authors and Affiliations

  1. Department of Toxicology, State University of Groningen, Ant. Deusinglaan 2, 9713, AW Groningen, The Netherlands

    K. Ensing & R. A. De Zeeuw

Authors
  1. K. Ensing
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  2. R. A. De Zeeuw
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Ensing, K., De Zeeuw, R.A. Does the tissue concentration in receptor binding studies change the affinity of the labelled ligand?. Pharmaceutisch Weekblad Scientific Edition 6, 241–244 (1984). https://doi.org/10.1007/BF01954552

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  • DOI: https://doi.org/10.1007/BF01954552

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