Optical Recording of Neuronal Activity in Brain Slices Stained with a Voltage-Sensitive Dye
Transcript
Take an immobilized mouse brain slice stained with a voltage-sensitive dye or VSD, fluorescent molecules that integrate into the neuronal membrane and respond to membrane potential changes.
Place the slice in a recording chamber.
Install the ground electrode for a baseline voltage reference.
Next, position the stimulating and recording electrodes on the slice.
Apply an electrical pulse.
The pulse stimulates the neurons, triggering voltage-gated sodium channel opening and sodium ion influx, leading to a membrane potential change.
This induces an action potential, measured by the recording electrode, and alters the VSD's fluorescent properties.
Expose the brain slice to a specific wavelength to excite the VSD and trigger fluorescence emission.
Post-stimulation, the sodium channels close while the voltage-gated potassium channels open, promoting potassium ion efflux.
This changes the membrane potential again and consequently alters the VSD's fluorescence.
Record the fluorescence in real-time to visually represent neuronal activity.
