The hippocampus sends efferent fibers to the subiculum, which projects to the entorinal cortex. Previous studies suggest that the hippocampal CA1 area may receive a projection back from the subiculum. This hypothesis was tested using whole cell recording from CA1 pyramidal cells while subicular neurons were selectively stimulated with focal flash photolysis of caged glutamate, which avoids stim...

Gamma frequency (30-80 Hz) oscillations are implicated in memory processing. Such rhythmic activity can be generated intrinsically in the CA3 region of the hippocampus from where it can propagate to the CA1 area. To uncover the synaptic mechanisms underlying the intrahippocampal spread of gamma oscillations, we recorded local field potentials, as well as action potentials and synaptic currents ...

BACKGROUND GABAergic interneurons in the hippocampal CA1 area are mutually communicated by gap junctions (GJs) composed of connexin36 (Cx36). We examined the role of Cx36 in CA1 in manifestation of kindled seizures and hippocampal kindling in rats. METHODS Quinine, as the specific blocker of Cx36, was injected into CA1, and kindled seizures severity was examined 10 min afterward. Moreover, qu...

The hippocampus is proposed to switch between memory encoding and retrieval by continually computing the overlap between what is expected and what is encountered. Central to this hypothesis is that area CA1 performs this calculation. However, empirical evidence for this is lacking. To test the theoretical role of area CA1 in match/mismatch detection, we had subjects study complex stimuli and th...

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...

objective: nano components are today’s new wonder material. however, the safety or toxicity of these components in humans is not yet clear. in a previous study we indicated that nano zno (nzno) has a stronger anxiolytic effect compared to the conventional zno (czno). the present study was designed to evaluate the intraperitoneal administration of an opioidergic receptor agonist and antagonist o...

The subiculum (SB) is the principal target of the axons of the CA1 pyramidal cells and serves as the final relay in the trisynaptic loop between the entorhinal cortex and the hippocampus. We have examined synaptic plasticity in the synaptic pathway between the CA1 pyramidal cells and the SB in hippocampal slices and compared it under the same experimental condition with the synaptic plasticity ...

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...

The mammalian hippocampus harbours neural circuitry that is crucial for associative learning and memory. The mechanisms that underlie the development and regulation of this complex circuitry are not fully understood. Our previous study established an essential role for the zinc finger protein Zbtb20 in the specification of CA1 field identity in the developing hippocampus. Here, we show that con...