No-Wash Dyes for Calcium Flux Measurement

• Published in: BioTechniques Vol. 34; no. 1; pp. 164 - 166
• Main Authors: Mehlin, Christopher, Crittenden, Carole, Andreyka, Jamie
• Format: Journal Article
• Language: English
• Published: Natick, MA Future Science Ltd 01.01.2003; Eaton
• Subjects: Astrocytoma - metabolism; Biological and medical sciences; Calcium - agonists; Calcium - metabolism; Calcium - pharmacokinetics; Calcium Channels - drug effects; Calcium Channels - metabolism; Diverse techniques; Dose-Response Relationship, Drug; fluo-4; Fluorescent Dyes; Fluorometry - instrumentation; Fluorometry - methods; Fundamental and applied biological sciences. Psychology; Hemoglobins; HT29 Cells - drug effects; HT29 Cells - metabolism; Humans; Molecular and cellular biology; Neurotensin - pharmacology; Probenecid; Quality Control; Sensitivity and Specificity; Signal Transduction; Staining and Labeling - methods; Substance P - pharmacology; Trypan Blue; Tumor Cells, Cultured; Binding protein; Signal transduction; Calcium ion; Fluorescent tracer; Flux; Receptor protein; Method; G protein
• ISSN: 0736-6205; 1940-9818
• DOI: 10.2144/03341dd03

Calcium flux measurement has become a key method in the investigation of G-protein coupled receptors. Central to this technique is the use of cell-permeable fluorescent dyes, such as Fluo-4, which increase in fluorescence markedly upon influx of calcium through membrane channels or release from intracellular stores. About 40% of G-protein coupled receptors (GPCRs) utilize G-proteins that stimulate calcium flux as a cellular signaling mechanism, and those that do not can be artificially coupled to calcium flux through the use of promiscuous G proteins (such as G alpha sub(16)) or through the use of chimeric G proteins. Stimulation of dye-loaded cells with ligand leads to a transient increase in fluorescence, a system that has proven applicability with a wide variety of GPCRs.