title: Calcium Uncaging with Visible Light.
abstract: We have designed a nitroaromatic photochemical protecting group that absorbs visible light in the violet-blue range. The chromophore is a dinitro derivative of bisstyrylthiophene (or BIST) that absorbs light very effectively (ε440 = 66,000 M(-1) cm(-1) and two-photon cross section of 350 GM at 775 nm). We developed a "caged calcium" molecule by conjugation of BIST to a Ca(2+) chelator that upon laser flash photolysis rapidly releases Ca(2+) in <0.2 ms. Using the patch-clamp method the optical probe, loaded with Ca(2+), was delivered into acutely isolated mouse cardiac myocytes, where either one- and two-photon uncaging of Ca(2+) induced highly local or cell-wide physiological Ca(2+) signaling events.
authors.affiliation: Department of Neuroscience, Mount Sinai School of Medicine , New York, New York 10029, United States.
authors.forename: Hitesh K
authors.initials: HK
authors.lastname: Agarwal
authors.affiliation: Department of Physiology, University of Bern , Bern CH 3012, Switzerland.
authors.forename: Radoslav
authors.initials: R
authors.lastname: Janicek
authors.affiliation: School of Chemistry and Biochemistry, Center for Organic Photonics and Electronics, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
authors.forename: San-Hui
authors.initials: SH
authors.lastname: Chi
authors.affiliation: School of Chemistry and Biochemistry, Center for Organic Photonics and Electronics, Georgia Institute of Technology , Atlanta, Georgia 30332, United States.
authors.forename: Joseph W
authors.initials: JW
authors.lastname: Perry
authors.affiliation: Department of Physiology, University of Bern , Bern CH 3012, Switzerland.
authors.forename: Ernst
authors.initials: E
authors.lastname: Niggli
authors.affiliation: Department of Neuroscience, Mount Sinai School of Medicine , New York, New York 10029, United States.
authors.forename: Graham C R
authors.initials: GC
authors.lastname: Ellis-Davies
mesh_terms: D017610:Calcium Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D002614:Chelating Agents / Q000737:chemistry; D004533:Egtazic Acid / Q000737:chemistry; D008027:Light; D055668:Photochemical Processes; D013876:Thiophenes / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D017610:Calcium Compounds; D002614:Chelating Agents; D013876:Thiophenes; D004533:Egtazic Acid