The effects of brief anoxic episodes on rat CA3 hippocampal neurons were studied with intracellular and extracellular techniques in the in vitro slice preparation. After repeated (3-7 times), brief (2-6 min duration each) applications of artificial cerebrospinal fluid (ACSF) saturated with 95% N2 and 5% CO2, electrical stimulation of various inputs to CA3 neurons, evoked an excitatory postsynap...

The distribution of glutamate receptors in the rat hippocampus was investigated 24 h after the social stress of confrontation with a dominant opponent. AMPA-type glutamate receptors were labeled with the antagonist [3H]CNQX, and NMDA-type receptors were labeled with the competitive antagonist [3H]CGP39653. Increased [3H]CGP39653 labeling was exclusively found in the CA3 stratum radiatum and a d...

Recent studies demonstrate that context-specific memory retrieval after extinction requires the hippocampus. However, the contribution of hippocampal subfields to the context-dependent expression of extinction is not known. In the present experiments, we examined the roles of areas CA1 and CA3 of the dorsal hippocampus in the context specificity of extinction. After pairing an auditory conditio...

Mossy fiber synapses on CA3 pyramidal cells are 'conditional detonators' that reliably discharge postsynaptic targets. The 'conditional' nature implies that burst activity in dentate gyrus granule cells is required for detonation. Whether single unitary excitatory postsynaptic potentials (EPSPs) trigger spikes in CA3 neurons remains unknown. Mossy fiber synapses exhibit both pronounced short-te...

Much of the work on forebrain ischemia in the hippocampus has focused on the phenomenon of delayed neuronal death in CA1. It is established that dentate granule cells and CA3 pyramidal cells are resistant to ischemia. However, much less is known about interneuronal involvement in CA3 or ischemic injury in the dentate hilus other than the fact that somatostatin neurons in the latter lose their i...

Memories can be recalled at different levels of resolution, from a detailed rendition of specific events within a single experience to a broad generalization across multiple related experiences. Here we provide evidence that neural representations reflecting the specificity or generality of memories are differentially represented along the dorsoventral axis of the CA3 area of the rat hippocampu...

Norepinephrine is an endogenous neurotransmitter distributed throughout the mammalian brain. In higher cortical structures such as the hippocampus, norepinephrine, via beta adrenergic receptor (AR) activation, has been shown to reinforce the cognitive processes of attention and memory. In this study, we investigated the effect of beta1AR activation on hippocampal cornu ammonis 3 (CA3) network a...

In mossy fiber synapses of the CA3 region of the hippocampus, long-term potentiation (LTP) is induced presynaptically by activation of cAMP-dependent protein kinase A (PKA). Rab3A is a synaptic vesicle protein that regulates vesicle fusion and is essential for mossy fiber LTP. Rab3A probably acts via two effector proteins, rabphilin and RIM, of which rabphilin is an in vitro substrate for PKA. ...

Temporal lobe epilepsy (TLE) is a form of refractory focal epilepsy, which includes latent period and chronic period. Microelectrode arrays capable multi-region detection neural activities are important for accurately identifying the epileptic focus pathogenesis mechanism in TLE. Here, we fabricated multi-shank MEAs to detect DG, hilus, CA3, CA1 TLE rat model. In rats, seizures were induced cha...