title: Analysis of potassium and calcium imaging to assay the function of opioid receptors.
abstract: As the activation of opioid receptors leads to the modulation of potassium and calcium channels, the ion imaging represents an attractive method to analyze the function of the receptors. Here, we describe the imaging of potassium using the FluxOR™ potassium ion channel assay, and of calcium using Fura-2 acetoxymethyl ester. Specifically, we (1) characterize the activation of the G-protein-coupled inwardly rectifying potassium 2 channel by agonists of μ- and δ-opioid receptors with the aid of the FluxOR™ assay in cultured mouse dorsal root ganglion neurons, and (2) describe calcium imaging protocols to measure capsaicin-induced transient receptor potential vanilloid 1 channel activity during opioid withdrawal in transfected human embryonic kidney 293 cells.
authors.affiliation: Klinik für Anästhesiologie und Operative Intensivmedizin, Freie Universität Berlin, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, Berlin, 12203, Germany, viola.spahn@charite.de.
authors.forename: Viola
authors.initials: V
authors.lastname: Spahn
authors.forename: Dinah
authors.initials: D
authors.lastname: Nockemann
authors.forename: Halina
authors.initials: H
authors.lastname: Machelska
mesh_terms: D000818:Animals; D002118:Calcium / Q000032:analysis*; D015220:Calcium Channels / Q000737:chemistry; D005727:Ganglia, Spinal / Q000378:metabolism; D006801:Humans; D051379:Mice; D008967:Molecular Biology / Q000379:methods; D009474:Neurons / Q000737:chemistry / Q000378:metabolism; D011188:Potassium / Q000032:analysis*; D015221:Potassium Channels / Q000737:chemistry; D011957:Receptors, Opioid / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D015220:Calcium Channels; D015221:Potassium Channels; D011957:Receptors, Opioid; D011188:Potassium; D002118:Calcium