title: Ligand characterization using microphysiometry.
abstract: This unit describes the use of a Cytosensor microphysiometer for functional characterization of an agonist and antagonist to a G protein-coupled receptor, the muscarinic M1 receptor. Concentration-response profiles are used to calculate values for the EC50 of the response of cells to the agonist and the pA2 value for the antagonist. Support protocols describe optimization of two aspects of this procedure: the duration of ligand exposure at a given concentration and the length of recovery time between the administration of two different concentrations of ligand to minimize the impact of desensitization. The Cytosensor microphysiometer allows the measurement of receptor activation in both adherent cells, such as the M1WT3 cells used here or in suspension cultures.
authors.affiliation: Molecular Devices Corporation, Sunnyvale, California, USA.
authors.forename: S
authors.initials: S
authors.lastname: Pitchford
mesh_terms: D000818:Animals; D016466:CHO Cells / Q000737:chemistry; D002217:Carbachol / Q000378:metabolism* / Q000494:pharmacology; D006224:Cricetinae; D003412:Cricetulus; D004305:Dose-Response Relationship, Drug; D006863:Hydrogen-Ion Concentration; D008024:Ligands; D008832:Microchemistry / Q000379:methods*; D018721:Muscarinic Agonists / Q000378:metabolism*; D018727:Muscarinic Antagonists / Q000378:metabolism*; D010890:Pirenzepine / Q000378:metabolism* / Q000494:pharmacology; D011522:Protons; D043643:Receptor, Muscarinic M1 / Q000819:agonists / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000187:drug effects / Q000378:metabolism; D014162:Transfection / Q000379:methods
chemical_list: D008024:Ligands; D018721:Muscarinic Agonists; D018727:Muscarinic Antagonists; D011522:Protons; D043643:Receptor, Muscarinic M1; D011993:Recombinant Fusion Proteins; D010890:Pirenzepine; D002217:Carbachol