Imaging synaptic inhibition in transgenic mice expressing the chloride indicator, Clomeleon.

Journal Article

We describe here a molecular genetic approach for imaging synaptic inhibition. The thy-1 promoter was used to express high levels of Clomeleon, a ratiometric fluorescent indicator for chloride ions, in discrete populations of neurons in the brains of transgenic mice. Clomeleon was functional after chronic expression and provided non-invasive readouts of intracellular chloride concentration ([Cl(-)](i)) in brain slices, allowing us to quantify age-dependent declines in resting [Cl(-)](i) during neuronal development. Activation of hippocampal interneurons caused [Cl(-)](i) to rise transiently in individual postsynaptic pyramidal neurons. [Cl(-)](i) increased in direct proportion to the amount of inhibitory transmission, with peak changes as large as 4 mM. Integrating responses over populations of pyramidal neurons allowed sensitive detection of synaptic inhibition. Thus, Clomeleon imaging permits non-invasive, spatiotemporally resolved recordings of [Cl(-)](i) in a large variety of neurons, opening up new opportunities for imaging synaptic inhibition and other forms of chloride signaling.

Full Text

Duke Authors

Cited Authors

  • Berglund, K; Schleich, W; Krieger, P; Loo, LS; Wang, D; Cant, NB; Feng, G; Augustine, GJ; Kuner, T

Published Date

  • December 2006

Published In

Volume / Issue

  • 35 / 4-6

Start / End Page

  • 207 - 228

PubMed ID

  • 18398684

International Standard Serial Number (ISSN)

  • 1559-7105

Digital Object Identifier (DOI)

  • 10.1007/s11068-008-9019-6

Language

  • eng

Conference Location

  • United States