Recording Whole-Cell Currents with GABA Puffing in a Mouse Brain Slice

Begin with a secured prefrontal cortical brain slice in an artificial cerebrospinal fluid, or aCSF, in the recording chamber of an electrophysiology setup.

This aCSF contains a sodium ion channel blocker, which inhibits sodium channels in neurons.

Position a puff micropipette filled with gamma-aminobutyric acid, or GABA, above a postsynaptic neuron.

Place an ionic solution-filled recording micropipette with an electrode near the same neuron.

Apply weak suction to create a tight seal with a small patch of the neuronal membrane.

Then, apply strong suction to disrupt the patched membrane, enabling access to the neuron's interior.

Deliver the GABA, an inhibitory neurotransmitter, which binds with a ligand-gated chloride channel on postsynaptic neurons.

This opens the channel and allows chloride ions to enter the neurons, generating an inhibitory postsynaptic current.

At a constant voltage, record the postsynaptic current. An increase in inhibitory postsynaptic current reflects GABA's role in neuronal activity inhibition.

Transfer a brain slice to the recording chamber using a Pasteur pipette with its fine tip cut to fit the size of the slice. Next, place a platinum slice anchor above t