Related Experiment Video
Updated: Jun 19, 2026
Investigating Long-term Synaptic Plasticity in Interlamellar Hippocampus CA1 by Electrophysiological Field Recording
Published on: August 11, 2019
Acute hyperexcitability differentially affects hippocampal neurogenesis features and spatial memory
Diana López-Ibarra1, Andrea Aguilar-Arredondo2,3, Verónica Gaytan-Zeron1
1Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, UNAM, Mexico City, Mexico.
Introduction:
Epileptic seizures induce aberrant adult hippocampal neurogenesis (AHN), yet how varying seizure intensities affect this process and associated memory functions remains unclear.
Methods:
Here we administered systemically a low (5 mg/kg) or a high (25 mg/kg) dose of kainic acid (KA) to induce acute hyperexcitability of differing severity in mice of both sexes (6 to 8 weeks-old) genetically labeled for Ascl1, which allowed to follow progenitor cells and their progeny in the dentate gyrus (DG). We recorded EEG, assessed spatial and contextual fear memory, and analyzed adult-born granule cells (abGCs) 32 days post-treatment.
Results:
High-dose KA produced more severe and prolonged seizures, increased mature abGCs with altered laminar positioning, and elevated dendritic spine density, whereas low-dose KA induced presynaptic bouton enlargement. Both doses impaired spatial location recognition but spared contextual fear memory.
Discussion:
These findings reveal that acute seizure severity differentially modulates morphological and synaptic features of abGCs and selectively disrupts hippocampal-dependent spatial memory, indicating that hyperexcitability exerts qualitative effects on neurogenesis and cognitive function.
