Practical Aspects of Radioligand Binding

Michael McKinney1, Rita Raddatz2

1 Mayo Clinic Jacksonville, Jacksonville, Florida, 2 Cephalon, Inc., West Chester, Pennsylvania
Publication Name:  Current Protocols in Pharmacology
Unit Number:  Unit 1.3
DOI:  10.1002/0471141755.ph0103s33
Online Posting Date:  July, 2006
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Radioligand binding has been used for many years to identify new binding sites, characterize receptors, and identify novel ligands. Although various techniques have been developed to improve the efficiency of preparing the biological source of the receptors and for detecting bound radioligand, the principles of the assays remain the same. This unit reviews theory and provides examples of the parameters that can be calculated from radioligand binding data to characterize ligandÔÇÉreceptor interactions. The important aspects of assay development and validation that allow meaningful interpretation are discussed. The selection of a radioligand, buffer and other assay components is critical to developing a useful binding assay. The nature of the binding interaction can also be probed by varying assay conditions.

Keywords: radioligand binding; filtration; membrane preparation; affinity; saturation binding; displacement

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Table of Contents

  • Fundamentals of Radioligand Binding Assays
  • Guidelines for Establishing a Radioligand Binding Assay
  • Analysis of Binding Data
  • Troubleshooting
  • Literature Cited
  • Figures
  • Tables
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Key References
   Kenakin, 2004. A pharmacology primer: Theory, application and methods. Elsevier, Inc., London, UK.
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