Measuring Neural Activity in a Mouse Brain Slice after Prolonged Incubation

Secure a mouse brain slice in a recording chamber, perfused with oxygenated aCSF after prolonged incubation.

The cells in the slice are loaded with a calcium indicator, facilitating intracellular calcium measurements.

Take a recording pipette comprising an electrode in an electrolyte  solution.

Identify a target neuron. Position the recording pipette with positive pressure on the cell membrane, creating a dimple.

Apply negative pressure to create a tight seal.

Further, apply negative pressure pulses, rupturing the membrane and establishing a whole-cell configuration .

Perfuse aCSF with a high potassium concentration, which depolarizes the neuron's membrane.

Depolarization opens sodium channels, triggering an action potential, which in turn activates voltage-gated calcium channels and allows calcium influx.

Calcium ions bind to the indicator, enhancing fluorescence, which can be visualized under suitable illumination.

The increase in intracellular fluorescence, caused by calcium influx following potassium application, indicates neuronal viability after prolonged incubation.