title: Maternal deprivation induces deficits in temporal memory and cognitive flexibility and exaggerates synaptic plasticity in the rat medial prefrontal cortex.
abstract: Early life adverse events can lead to structural and functional impairments in the prefrontal cortex (PFC). Here, we investigated whether maternal deprivation (MD) alters PFC-dependent executive functions, neurons and astrocytes number and synaptic plasticity in adult male Long-Evans rats. The deprivation protocol consisted of a daily separation of newborn Long-Evans pups from their mothers and littermates 3h/day postnatal day 1-14. Cognitive performances were assessed in adulthood using the temporal order memory task (TMT) and the attentional set-shifting task (ASST) that principally implicates the PFC and the Morris water maze task (WMT) that does not essentially rely on the PFC. The neurons and astrocytes of the prelimbic (PrL) area of the medial PFC (mPFC) were immunolabelled respectively with anti-NeuN and anti-GFAP antibodies and quantified by stereology. The field potentials evoked by electrical stimulation of ventral hippocampus (ventral HPC) were recorded in vivo in the PrL area. In adulthood, MD produced cognitive deficits in two PFC-dependent tasks, the TMT and ASST, but not in the WMT. In parallel, MD induced in the prelimbic area of the medial PFC an upregulation of long-term potentiation (LTP), without any change in the number of neurons and astrocytes. We provide evidence that MD leads in adults to an alteration of the cognitive abilities dependent on the PFC, and to an exaggerated synaptic plasticity in this region. We suggest that this latter phenomenon may contribute to the impairments in the cognitive tasks.
authors.affiliation: INSERM, UMRs, Physiopathologie des Maladies du Système Nerveux Central, Paris, France.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Baudin
authors.forename: Kévin
authors.initials: K
authors.lastname: Blot
authors.forename: Catherine
authors.initials: C
authors.lastname: Verney
authors.forename: Lucie
authors.initials: L
authors.lastname: Estevez
authors.forename: Julie
authors.initials: J
authors.lastname: Santamaria
authors.forename: Pierre
authors.initials: P
authors.lastname: Gressens
authors.forename: Bruno
authors.initials: B
authors.lastname: Giros
authors.forename: Satoru
authors.initials: S
authors.lastname: Otani
authors.forename: Valérie
authors.initials: V
authors.lastname: Daugé
authors.forename: Laurent
authors.initials: L
authors.lastname: Naudon
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000502:physiology; D001288:Attention / Q000502:physiology; D002452:Cell Count; D003071:Cognition / Q000502:physiology*; D004558:Electric Stimulation; D056344:Executive Function / Q000502:physiology; D005260:Female; D006624:Hippocampus / Q000503:physiopathology; D008297:Male; D008426:Maternal Deprivation; D018782:Maze Learning / Q000502:physiology*; D008569:Memory Disorders / Q000503:physiopathology*; D009434:Neural Pathways / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D017397:Prefrontal Cortex / Q000503:physiopathology*; D051381:Rats; D020318:Rats, Long-Evans; D012718:Set, Psychology; D009435:Synaptic Transmission / Q000502:physiology