Impairments to the Giant Depolarizing Potentials After the Third Trimester Equivalent Ethanol Exposure in the Neonatal Rat
Ethanol exerts multiple adverse effects in the developing hippocampus resulting in the life-long neurological and behavioral deficits. However, the early disturbances in the hippocampal network function after exposure to ethanol remain largely unknown. Here, we examined the properties of the neonatal CA3 hippocampal network-driven giant depolarizing potentials using extracellular recordings of the local field potential and multiple units from the hippocampal slices prepared from the 5–11-day-old rats treated by ethanol in vivo (6 g/kg, intraperitoneally), 12 h before the slice preparation. Activity in hippocampal slices from the ethanol-treated animals displayed several abnormalities including a threefold increase in overall neuronal firing and profound, by nearly sevenfold, reduction of synchronization of CA3 units in giant depolarizing potentials. Thus, alterations in the hippocampal network function emerge shortly after the ethanol exposure and manifest in the enhanced excitation and severe impairments to the giant depolarizing potentials.
KeywordsAlcoholism Fetal alcohol syndrome Hippocampus Giant depolarizing potentials Neonate
This work was supported by INSERM (LIA to RK), the Program of Competitive Growth of Kazan Federal University and the subsidy allocated to Kazan Federal University for the state assignment in the sphere of scientific activities.
Compliance with Ethical Standards
This work has been carried out in accordance with EU Directive 2010/63/EU for animal experiments and all the protocols were approved by INSERM (N007.08.01) and KSMU (N9-2013).
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