Functional Receptor Assays

[35S]-GTPγS Autoradiography

[35S]-GTPγS receptor binding is used to study the distribution and functional activation of neurotransmitter receptors (GPCRs) in tissue sections (rodent, non-human primate & human). This technique combines the advantages of receptor autoradiography and [35S]-GTPγS binding, providing anatomical and functional (EC50 & EMAX) information. Upon binding of an agonist, activated GPCRs can be visualized in the sample.

Functional Receptor Autoradiography can be used to:

  1. Determine the pharmacological values of potency (EC50) & efficacy (EMAX) of the ligand to activate the GPCR of interest
  2. Visualize regional differences of activated GPCRs by a ligand
  3. Determine if the ligand is an agonist or antagonist

[35S]-GTPγS Binding

[35S]-GTPγS binding, also known as a GTP exchange assay, is a powerful method used to measure the activation of G protein-coupled receptors (GPCRs) by a ligand.

[35S]-GTPγS binding can be used to:

  1. Determine if a ligand can activate a GPCR of interest
  2. Determine pharmacological values of potency (EC50) & efficacy (EMAX)
  3. Determine if a ligand is an agonist or antagonist
  4. Screen for agonists or antagonists
Functional Binding Assays
Ref# Receptor Agonist Antagonist
FBA001 Serotonin 5-HT1A Serotonin WAY 100635
FBA002 Serotonin 5-HT1A 8-OH-DPAT WAY 100635
FBA003 Serotonin 5-HT2C Serotonin SB242084
FBA004 Adenosine A1 CPA DPCPX
FBA018 Adenosine A3 IB-MECA MRS 1220
FBA005 Adrenergic a2A Clonodine Yohimbine
FBA019 Adrenergic a2B UK 14304 Yohimbine
FBA020 Adrenergic a2C UK 14304 Yohimbine
FBA006 Cannabinoid CB1 CP 55940 AM 251
FBA007 Cannabinoid CB2 CP 55940 AM 630
FBA021 Chemokine CCR5 MIP-1β Vicriviroc
FBA008 Dopamine D1 Dopamine (+)-Butaclamol
FBA009 Dopamine D2 Dopamine Spiperone
FBA010 Dopamine D3 Dopamine Spiperone
FBA011 Histamine H1 Histamine Pyrilamine
FBA022 Muscarinic M1 Oxotremorine M Pirenzepine
FBA023 Muscarinic M4 4-DAMP McN-A-343
FBA012 d Opioid DPDPE Naltrindole
FBA013 k Opioid U-69593 nor-Binaltorphimine
FBA014 m Opioid DAMGO Naloxone
FBA015 Nociceptin ORL1 Nociceptin BAN ORL24
FBA017 Sphingosine-1-Phosphate SP1P W146