Volume 13 Supplement 1
Modeling the chemical dynamics of chloride ion indicators
© Redford et al; licensee BioMed Central Ltd. 2012
Published: 16 July 2012
Fluorescent indicators have shown promise as a relatively non-invasive probe to measure cytosolic ion concentrations in brain slices and neuron cultures using microscopy imaging. Most fluorescent ion indicators bind selectively with a certain ion in solution causing a decrease in fluorescence in a process known as quenching. Under steady state conditions, a fluorescence measurement, made at a specific point and time, is directly related to the local ion concentration at the same point and time, typically via the Stern-Volmer relationship. However, this is usually no longer true under the dynamic conditions inside a cell when transmembrane currents are active.
In our research, we are interested in measuring chloride (Cl-) channel currents because of their implication in substance abuse mechanisms. Useful probes have been found in Cl- sensitive dyes, such as N-(6-methoxyquinolyl) acetoethyl ester (MQAE) , and 6-methoxy-N-ethylquinolinium (MEQ) , and variants of the Yellow Fluorescent Protein (YFP) useful as a Cl- biosensor in dendritic compartments .
- Marandi N, Konnerth A, Garaschuk O: Two-photon chloride imaging in neurons of brain slices. Pflugers Arch - Eur J of Physiol. 2002, 445: 357-365. 10.1007/s00424-002-0933-7.View ArticleGoogle Scholar
- Borst A, Abarbanel HDI: Relating a calcium indicator signal to the unperturbed calcium concentration time-course. Theor Biol Med Model. 2007, 4: 7-10.1186/1742-4682-4-7.PubMed CentralView ArticlePubMedGoogle Scholar
- Inglefield JR, Schwartz-Bloom RD: Fluorescence imaging of changes in intracellular chloride in living brain slices. Methods. 1999, 18 (2): 197-203. 10.1006/meth.1999.0772.View ArticlePubMedGoogle Scholar
- Waseem T, Mukhtarov M, Buldakova S, Medina I, Bregestovski P: Genetically encoded Cl-Sensor as a tool for monitoring of Cl-dependent processes in small neuronal compartments. J Neurosci Methods. 2010, 193 (1): 14-23. 10.1016/j.jneumeth.2010.08.002.View ArticlePubMedGoogle Scholar