The rapid encoding of contextual memory requires the CA3 region of the hippocampus, but the necessary genetic pathways remain unclear. We found that the activity-dependent transcription factor Npas4 regulates a transcriptional program in CA3 that is required for contextual memory formation. Npas4 was specifically expressed in CA3 after contextual learning. Global knockout or selective deletion ...

CA3-CA3 recurrent excitatory synapses are thought to play a key role in memory storage and pattern completion. Whether the plasticity properties of these synapses are consistent with their proposed network functions remains unclear. Here, we examine the properties of spike timing-dependent plasticity (STDP) at CA3-CA3 synapses. Low-frequency pairing of excitatory postsynaptic potentials (EPSPs)...

Distinct subtypes of ionotropic glutamate receptors can segregate to specific synaptic inputs in a given neuron. Using functional mapping by focal glutamate uncaging in CA3 pyramidal cells (PCs), we observe that kainate receptors (KARs) are strictly confined to the postsynaptic elements of mossy fibre (mf) synapses and excluded from other glutamatergic inputs and from extrasynaptic compartments...

objective(s):this study was carried out to evaluate the effect of maternal morphine exposure during gestational and lactation period on pyramidal neurons of hippocampus in 18 and 32 day mice offspring. materials and methods: thirty female mice were randomly allocated into cases and controls. in case group, animals received morphinesulfate 10 mg/kg.body weight intraperitoneally during 7 days bef...

In this work, a series of compounds in the CaO-CoOx-ErOy ternary oxide system were synthesized air at 885 °C, using high temperature solid-phase synthesis method. The phase boundary each solid solution region was determined by X-ray powder diffraction techniques. diagram °C includes three solutions: (Ca3−xErx)Co4O9−z (0 ≤ x 0.9), (Ca3−xErx)Co2O6−z 1.25), and (Er1−xCax)CoO3−z 0.33). Four three-p...

The perforant path constitutes the primary projection system relaying information from the neocortex to the hippocampal formation. Long-term synaptic potentiation (LTP) in the perforant path projections to the dentate gyrus is well characterized. However, surprisingly few studies have addressed the mechanisms underlying LTP induction in the direct perforant path projections to the hippocampus. ...

Advanced ageing is associated with hippocampal deterioration and mild cognitive decline. The hippocampal subregion CA3 stratum lucidum (CA3-SL) receives neuronal inputs from the giant mossy fibre boutons of the dentate gyrus, but relatively little is known about the integrity of this synaptic connection with ageing. Using serial electron microscopy and unbiased stereology, we examined age-relat...

The predominant excitatory synaptic input to the hippocampus arises from entorhinal cortical axons that synapse with dentate granule cells, which in turn synapse with CA3 pyramidal cells. Thus, two highly excitable brain areas – the entorhinal cortex and the CA3 field – are separated by dentate granule cells, which have been proposed to function as a gate or filter. However, unlike rats, primat...

The CA3 region of the hippocampus has long been proposed as an autoassociative network performing pattern completion on known inputs. The dentate gyrus (DG) region is often proposed as a network performing the complementary function of pattern separation. Neural models of pattern completion and separation generally designate explicit learning phases to encode new information and assume an ideal...

Subregion-dependent differences in the role of the hippocampus in information processing exist. Recently, it has emerged that a special relationship exists between the expression of persistent forms of synaptic plasticity in hippocampal subregions and the encoding of different types of spatial information. Little is known about this type of information processing at CA3 synapses. We report that...