title: Fura 2 determination of [Ca2+]i in isolated perfused heart using R wave-gated electromechanical shutters.
abstract: We describe a novel and relatively inexpensive spectrofluorescence system that supplies rapidly alternating wavelengths to either a standard cuvette or an isolated perfused heart. Its use is illustrated by determining changes in cytosolic intracellular Ca2+ concentration ([Ca2+]i) by using the Ca(2+)-sensitive fluorescent dye fura 2 in a rabbit heart preparation. The system uses two precision electromechanical shutters (capable of gating with respect to the electrocardiographic R wave for signal averaging) allowing alternate fura 2 excitation wavelengths (340 and 380 nm) without moving optical components and uses a fiber optic for conducting excitation and collecting epifluorescence. Sample recordings tracing the [Ca2+]i transient in an entire cardiac cycle and in capturing specific isolated regions (diastole and systole) of the cycle are presented. Limitations of this low-cost but easily implemented system are discussed.
authors.affiliation: Division of Cardiothoracic Surgery, New England Deaconess Hospital, Boston, Massachusetts 02215.
authors.forename: D P
authors.initials: DP
authors.lastname: Chen
authors.forename: E
authors.initials: E
authors.lastname: Jimenez
authors.forename: K
authors.initials: K
authors.lastname: Ataka
authors.forename: S
authors.initials: S
authors.lastname: Levitsky
authors.forename: H
authors.initials: H
authors.lastname: Feinberg
mesh_terms: D000818:Animals; D002118:Calcium / Q000032:analysis*; D003600:Cytosol / Q000737:chemistry; D003971:Diastole; D004562:Electrocardiography; D005336:Fiber Optic Technology; D016257:Fura-2 / Q000032:analysis* / Q000737:chemistry; D066298:In Vitro Techniques; D008297:Male; D009206:Myocardium / Q000737:chemistry*; D055100:Optical Fibers; D011817:Rabbits; D012984:Software; D013050:Spectrometry, Fluorescence; D013599:Systole
chemical_list: D002118:Calcium; D016257:Fura-2