BACKGROUND AND PURPOSE I studied the mechanism of postischemic neuronal degeneration in the hippocampus by an electrophysiological method. METHODS Sequential changes of field potentials evoked by perforant path stimulation in the dentate gyrus and the CA1 region of the hippocampus were evaluated in spontaneously hypertensive rats up to 7 days after transient global ischemia induced by bilater...

Since neuronal excitability is sensitive to changes in extracellular pH and there is regional diversity in the changes in extracellular pH during neuronal activity, we examined the activity-dependent extracellular pH changes in the CA1 region and the dentate gyrus. In vivo, in the CA1 region, recurrent epileptiform activity induced by stimulus trains, bicuculline, and kainic acid resulted in bi...

The tumor suppressor p63 is one of p53 family members and plays a vital role as a regulator of neuronal apoptosis in the development of the nervous system. However, the role of p63 in mature neuronal death has not been addressed yet. In this study, we first compared ischemia-induced effects on p63 expression in the hippocampal regions (CA1-3) between the young and adult gerbils subjected to 5 m...

The activity of dopamine (DA)-containing neurons in the ventral tegmental area (VTA) is a key mechanism in mesolimbic reward processing that has modulatory effects on different diencephalic structures like hippocampus (HIP), and receives inhibitory feedback and excitatory feed forward control. In addition, within the hippocampus, DA receptors are mostly located in the dorsal part (CA1) and dopa...

Temporal lobe epilepsy (TLE) in humans and animals is associated with axonal sprouting of glutamatergic neurons and neosynaptogenesis in the hippocampal formation. We examined whether this plasticity of excitatory pathways contributes to an increased level of glutamatergic excitation in the CA1 region of rats experiencing chronic spontaneous limbic seizures following kainic acid or pilocarpine ...

Epilepsy is one of the common disorders in human community. Clinical observations have shown that epileptic patients have often difficulty in learning and memory. Kindling is a laboratory model for studying epilepsy and its complications. This experiment was designed to study the effect of chemical kindling on Schaffer collateral-CA1 pyramidal cell synaptic transmission using pentylenetetrazole...

Two days following one-week administration of the benzodiazepine, flurazepam (FZP), rats exhibit anticonvulsant tolerance in vivo, while reduced GABA(A) receptor-mediated inhibition and enhanced EPSP amplitude are present in CA1 pyramidal neurons in vitro. AMPA receptor (AMPAR)-mediated synaptic transmission in FZP-treated rats was examined using electrophysiological techniques in in vitro hipp...

background and objectives: study of deleterious effect of neurotoxins on the animals' brain is a fascinating research plan. in this project, the damage effect of colchicine on the hippocampal cornu ammonis 1 (ca1) was examined by the studying the hippocampal tissue. materials and methods: injections of colchicine (1-75 μg/rat, intra- hippocampal ca1) were performed in cannulated male wistar rat...

Sharp-wave ripples (SPW-Rs) in the hippocampus are implied in memory consolidation, as shown by observational and interventional experiments. However, the mechanism of their generation remains unclear. Using two-dimensional silicon probe arrays, we investigated the propagation of SPW-Rs across the hippocampal CA1, CA2, and CA3 subregions. Synchronous activation of CA2 ensembles preceded SPW-R-r...

Recent studies have shown that place cells in the hippocampal CA1 region fire in a sequence sensitive manner. In this study we tested if hippocampal CA3 and CA1 regions can give rise to the sequence sensitivity. We used a two-layer CA3-CA1 hippocampal model that consisted of Hodgkin-Huxley style neuron models. Sequential input signals that mimicked signals projected from the entorhinal cortex g...