Summary
For equilibrium binding isotherms of radioreceptor assays, the affinity spectrum is defined as a plot of the number of binding sites against their corresponding dissociation constants. A numerical procedure for direct calculation of affinity spectra from untransformed binding data is presented and illustrated with experimental values. The advantage of the new method in comparison to non-linear regression analysis is the fact that no starting values and mathematical models have to be supplied and that statistical assessment of the results is straightforward from a detailed graphical display of a likelihood function. Affinity spectra thus show directly all information formerly obtained by means of both graphical plots and regression analysis.
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Abbreviations
- DAGO:
-
DAla2, MePhe4, Gly(ol)5-enkephalin
- GppNHp:
-
guanyl-5′yl-imidodiphosphat
- ICYP:
-
(±)-3-[125Iodo]cyanopindolol
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Tobler, H.J., Engel, G. Affinity spectra: A novel way for the evaluation of equilibrium binding experiments. Naunyn-Schmiedeberg's Arch. Pharmacol. 322, 183–192 (1983). https://doi.org/10.1007/BF00500763
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DOI: https://doi.org/10.1007/BF00500763