We have re-examined the hippocampal lamellar organization of the CA3-to-CA1 connection. Based on a new technique with electrophysiological quantification of Schaffer collateral density, and a review of recent literature, we conclude that the lamellar organization remains a useful concept for understanding hippocampal connectivity. Using a sheet-like hippocampal preparation, containing the whole...

introduction: considering the antiepileptogenic effects of repeated transcranial magnetic stimulation (rtms), the effect of rtms applied during amygdala kindling on spontaneous activity of hippocampal ca1 pyramidal neurons was investigated. materials and methods: a tripolar electrode was inserted in basolateral amygdala of male wistar rats. after a recovery period, animals received daily kindli...

Introduction: Donepezil (DON), an Acetylcholinesterase Inhibitor (AChEI), is widely used in the treatment of Alzheimer’s Disease (AD). The current study aimed at evaluating the effect of donepezil hydrochloride on pyramidal neuron response in CA1 region of a rat model of AD. Methods: In the current experimental study, adult male Wistar rats were randomly divided into four groups: Nucleus Basal...

Stochastic resonance (SR) in a hippocampal network model was investigated. The hippocampal model consists of two layers, CA3 and CA1. Pyramidal cells in CA3 are connected to pyramidal cells in CA1 through Schaffer collateral synapses. The CA3 network causes spontaneous irregular activity (broadband spectrum peaking at around 3 Hz), while the CA1 network does not. The activity of CA3 causes memb...

Hippocampal neuronal activity distinguishes separate events that share common elements. Here, we examined whether the capacity to disambiguate overlapping experiences is an exclusive feature of hippocampal processing or whether information processing one stage earlier in the hippocampal system also disambiguates common elements of distinct experiences. We compared the spatial firing patterns of...

Mammalian target of rapamycin (mTOR) has an important role in various biological processes in cells. In the present study, we investigated temporal changes in mTOR and phosphorylated-mTOR (p-mTOR) expressions in the rat hippocampal CA1 region following chronic cerebral hypoperfusion (CCH) induced by permanent bilateral common carotid arteries occlusion (2VO). The mTOR immunoreactivity in the py...

Delayed and selective neuronal damage was caused in the CA1 sector of hippocampus following 5 min of transient cerebral ischemia in gerbils. We investigated the immunohistochemical alterations of apoptosis-related proteins such as bcl-2α, bcl-xs/l, bax, cytochrome c, and active caspase 3 and TUNEL staining in the hippocampus at 1 and 5 hr and 1, 2, 5 and 14 days after transient cerebral ischemi...

Stress has deleterious effects on brain, body, and behavior in humans and animals alike. The present work investigated how 30-min acute photic stress exposure impacts on spatial information processing in the main sub-regions of the dorsal hippocampal formation [CA1, CA3, and dentate gyrus (DG)], a brain structure prominently implicated in memory and spatial representation. Recordings were perfo...

Ischemic preconditioning elicited by a non-fatal brief occlusion of blood flow has been applied for an experimental therapeutic strategy against a subsequent fatal ischemic insult. In this study, we investigated the neuroprotective effects of ischemic preconditioning (2-minute transient cerebral ischemia) on calbindin D28k immunoreactivity in the gerbil hippocampal CA1 area following a subseque...

Long-term potentiation (LTP) is a form of activity-dependent plasticity that occurs during learning. Potassium channels are the most diverse group of all ion channels that related to synaptic plasticity. Small-conductance calcium-activated potassium channels (SKs) are found in hippocampal CA1 neurons and by inhibiting of postsynaptic potentials are involved in synaptic transmission impairment. ...