Related Experiment Video
Updated: Aug 24, 2026

Neural Activity Propagation in an Unfolded Hippocampal Preparation with a Penetrating Micro-electrode Array
Published on: March 27, 2015
Valproate reduced synaptic activity increase induced by 4-aminopyridine at the hippocampal CA3-CA1 synapse
Eduardo D Martín1, Miguel A Pozo
1Brain Mapping Unit, Pluridisciplinary Institute, UCM, Madrid, Spain. eduardo.martin@uclm.es
Purpose:
We investigated the effects of valproate (VPA) on excitatory synaptic transmission changes induced by 4-aminopyridine (4-AP) to determine whether the antiepileptic effects shown by VPA can be ascribed to a modulation of spontaneous excitatory postsynaptic currents (sEPSCs) in the CA3-CA1 synapse.
Methods:
Rat hippocampal slices were prepared and maintained in vitro with standard methods. Whole-cell current and voltage-clamp recordings were obtained from CA1 pyramidal neurons by using the "blind" patch-clamp technique in an immersion recording chamber. Increase in the spontaneous excitatory synaptic activity was induced by addition of 4-AP to the medium.
Results:
Perfusion with VPA significantly counteracted the increase of frequency and amplitude of the sEPSCs induced by application of 4-AP and suppressed the epileptiform activity.
Conclusions:
We conclude that VPA decreases the 4-AP-induced enhancement of excitatory synaptic activity at the CA3-CA1 synapse, and that this reduction of excitation input to CA1 contributes to the anticonvulsant effects of VPA.
More Related Videos
Related Concept Videos
Integration of Synaptic Events
Ligand-Gated Ion Channel Receptor: Gating Mechanism
Antiepileptic Drugs: Modulators of Neurotransmitter Release Mediated by SV2A Protein
SV2A is a transmembrane glycoprotein located predominantly in the brain, modulating the release of neurotransmitters for neuronal communication. Both levetiracetam and brivaracetam exhibit a high affinity for...
Long-term Depression
Calcium Ion Concentration Mechanism
If over time, all...

