Recording of Induced Seizures through Electroencephalography in Freely Moving Rat Pups

Take a freely moving rat pup implanted with recording electrodes in the hippocampus and a reference electrode in the prefrontal cortex that establishes a baseline signal for comparison.

Connect the electrodes to a data acquisition system to record electrical activity.

Presynaptic neurons release neurotransmitters at synapses, which bind to receptors on postsynaptic neurons. Neurotransmitter binding induces ion influx, altering the membrane potential and generating postsynaptic potentials or PSPs.

The recording electrodes extracellularly capture summed PSPs from a neuronal population as electroencephalogram, or EEG, signals.

Intraperitoneally administer a seizure-inducing neurotoxin that binds to excitatory neurotransmitter receptors on postsynaptic neurons.

The toxin persistently activates the receptors, allowing continuous cation influx. This generates successive PSPs that reach the threshold and continuously trigger action potentials.

The continuous firing of action potentials across neuronal networks results in synchronized bursts of electrical activity termed epileptic seizures.

Monitor the neurotoxin-induced seizure through the EEG patterns.

After the recovery period, house the pup alone to make recordings for about 10 minutes so that the pup may become familiar with the environment. Connect the electrodes to an amplifier, and connect the amplifier to an AD converter attached to a computer. Be careful not to tangle these connections.

Next, on the data acquisition unit, select a sampling rate of at least 10,000 hertz for recording, and check for proper data transmission. Collect a baseline recording. After taking a baseline recording, inject the pup intraperitoneally with kainic acid to induce epileptic seizures. 15 minutes after the injection, observe and record the epileptic discharges.