Imaging synaptic inhibition with the genetically encoded chloride indicator Clomeleon

Area of Science:

• Neuroscience
• Molecular Biology
• Biochemistry

Background:

• Imaging brain excitatory processes is established, but visualizing synaptic inhibition remains challenging.
• Synaptic inhibition primarily involves transmembrane chloride ion (Cl(-)) fluxes.
• Directly imaging intracellular chloride concentration ([Cl(-)](i)) offers a pathway to visualize inhibition dynamics.

Purpose of the Study:

• To present a protocol for imaging synaptic inhibition in the brain.
• To utilize Clomeleon, a genetically encoded chloride indicator, for monitoring neuronal [Cl(-)](i).
• To enable visualization of the spatiotemporal dynamics of neural inhibition.

Main Methods:

• Employing Clomeleon, a genetically encoded indicator, for chloride ion sensing.
• Preparing brain slices from Clomeleon transgenic mice for imaging experiments.
• Developing and outlining procedures for monitoring neuronal [Cl(-)](i) in real-time.

Main Results:

• Successfully demonstrated the use of Clomeleon for imaging intracellular chloride levels.
• Established a protocol applicable to brain slices, with potential for cultured cells.
• Provided a method to visualize the dynamics of synaptic inhibition.

Conclusions:

• Clomeleon serves as an effective tool for imaging synaptic inhibition by monitoring intracellular chloride concentration.
• The described protocol facilitates the visualization of neural inhibition dynamics in brain slices.
• This technique offers a valuable approach for studying inhibitory neurotransmission in the brain.