Hippocampal dentate gyrus

Hippocampal dentate gyrus (DG) is essential for encoding highly similar inputs into distinct neural representations. This function is mainly attributed to the sparsely firing excitatory granule cells. It is not known how excitatory DG neurons modify their firing patterns in response to different conditions, to facilitate learning. We studied the activity of excitatory DG neurons during discrimination fear conditioning task (FC) using in vivo one-photon calcium imaging in adult, healthy C57/black mice. We compared learning in males (n = 6) and females (n = 6) and further, in voluntarily running

…with mTOR hyperactivity within the hippocampal formation and cognitive deficits, particularly pertaining to pattern separation and episodic memory. The hippocampal dentate gyrus (DG) subregion is crucial for gating the flow and separating the patterns of cortical information inputs, transmitting them via DG granule cell mossy

…the subventricular zone (SVZ) and the hippocampal dentate gyrus (DG). Caffeine, the most widely used psychostimulant, is a potent non-selective adenosine receptor antagonist. Though the adenosinergic system has been shown to regulate adult brain plasticity, caffeine impact on postnatal neurogenesis and synaptogenesis remains elusive. Thus, the main goal of this work was to dissect caffeine effects on the differentiation and maturation of postnatal NSCs into neurons.Our results indicate

…niches, the sub-ventricular zone and hippocampal dentate gyrus, where they produce olfactory bulb interneurons and dentate gyrus granule cells throughout life. In specific conditions the genesis of new neurons can occur also outside these niches in the adult brain parenchyma. This ectopic neurogenesis is prominent in the striatum where it occurs in both physiologic, in adult rabbits and adolescent guinea pigs, or pathologic conditions, such as mouse models of both progressive and acute neuronal degeneration.

Neuronal network imbalance and synaptic dysfunction both critically contribute to cognitive decline in AD. Network imbalance is increasingly recognized as an early characteristic of AD, which might precede and drive clinical symptoms. Early alterations in parvalbumin (PV+) interneurons contribute to this network dysfunction in AD mouse models. However, to what extent this shapes how memories are stored within the brain and drives cognitive decline remains to be determined. Our objective is to investigate synaptic, local, and network imbalances in AD, as well as their mutual dependence.We used

Background: The complexity of neurodegenerative and mood disorders necessitates innovative therapeutic strategies beyond current treatments. This study explores the combined therapeutic potential of Galanin receptor 2 (GALR2) and Neuropeptide Y Y1 receptor (Y1R) agonists, administered intranasally, on spatial memory, antidepressant-like behavior, and neurogenesis in adult rats.Methods: The investigation employed intranasal co-delivery of GALR2 agonist M1145 and Y1R agonist to adult rats, examining spatial memory through the object-in-place task and antidepressant-like effects via the Forced Sw

…axonal muscarinic receptors in hippocampal dentate gyrus granule neurons to persistently lower the action potential (AP) threshold and enhance neuronal excitability1. This was due to a sustained increase in T-type Ca2+ channel activity resulting in elevated basal Ca2+ levels which inhibited KV7 channels. The intracellular mechanism coupling axonal muscarinic receptors to T-type Ca2+ channels remains unknown. We investigated this by making electrophysiological r

Experiences are encoded in sparse neuronal ensembles that can be defined by the transcription activation of immediate-early genes such as Fos and Npas4. The Fos+ and Npas4+ neuronal ensembles within an engram have been reported to recruit distinct synaptic plasticity mechanisms. However, it remains unknown whether and how Fos- and Npas4-mediated synaptic plasticity support memory consolidation. Here we provide experimental and computational evidence that Fos+ and Npas4+ neuronal ensembles coordinate different excitatory and inhibitory synaptic plasticity mechanisms to promote memory consolidat

The hippocampal dentate gyrus (DG) to CA3 pathway plays a key role in encoding new experiences that are ultimately consolidated in the anterior cingulate cortex (ACC). Experience-dependent changes among excitatory neurons in the DG ‒ CA3 circuit have been intensely studied. However, DG cell axons innervate not only CA3 pyramidal neurons but also inhibitory, parvalbumin positive interneurons (PV IN) to provide strong feed-forward inhibition (FFI) onto CA3 pyramidal neurons. Following learning, FFI onto CA3 is temporarily increased which may be a key element for consolidation and long-term memor