The extent to which neocortical pyramidal cells function as a local network is determined by the strength and probability of their connections. By mapping connections between pyramidal cells we show here that in a local network of about 600 pyramidal cells located within a cylindrical volume of 200 microm x 200 microm of neocortical layer 2/3, an individual pyramidal cell receives synaptic inpu...

Objective(s):Global cerebral ischemia-reperfusion injury causes loss of pyramidal cells in CA1 region of hippocampus. In this study, we investigated the possible neuroprotective effects of the ethanol extract of Cyperus rotundus (EECR) on a model of global transient ischemia in rat, by evaluating the pathophysiology of the hippocampal tissue and spatial memory. Materials and Methods: Treatment ...

Since branching region of an active nerve fiber is an abrupt widening of the structure, two concepts emerge: first, the stimulating current must be sufficient to raise the outgrowing fibers above the thresh¬old, and secondly, the stimulating current will be divided in proportion to the characteristic admittance of the branches. On the other hand, blocking of the nerve impulse in this region is ...

Since branching region of an active nerve fiber is an abrupt widening of the structure, two concepts emerge: first, the stimulating current must be sufficient to raise the outgrowing fibers above the thresh¬old, and secondly, the stimulating current will be divided in proportion to the characteristic admittance of the branches. On the other hand, blocking of the nerve impulse in this region is ...

The hypothesis that recurrent inhibition in the hippocampus is mediated by interneurons was tested with simultaneous intracellular recordings from the CA1 region of guinea pig hippocampal slices in vitro. In recordings from 101 pairs of pyramidal cells, no interactions were detected in 87% of the pairs. In 13% of the pyramidal cell pairs, spike trains induced in one cell caused inhibitor postsy...

Extracellular population responses are largely preferred for the study of long-term potentiation (LTP). The effect of Mg2+-free medium on changes in activity and plasticity of Schaffer collateral-CA1 pyramidal cell synapses was examined. Hippcampal slices from cysteamine-treated (200 mg/kg, s.c.) and saline-injected (1 ml/kg, s.c.) albino rats were perfused with ACSF. Population spikes (PS) wer...

Extracellular population responses are largely preferred for the study of long-term potentiation (LTP). The effect of Mg2+-free medium on changes in activity and plasticity of Schaffer collateral-CA1 pyramidal cell synapses was examined. Hippcampal slices from cysteamine-treated (200 mg/kg, s.c.) and saline-injected (1 ml/kg, s.c.) albino rats were perfused with ACSF. Population spikes (PS) wer...

Both circuit and single-cell properties contribute to network rhythms. In vitro, pyramidal cells exhibit theta-band membrane potential (subthreshold) resonance, but whether and how subthreshold resonance translates into spiking resonance in freely behaving animals is unknown. Here, we used optogenetic activation to trigger spiking in pyramidal cells or parvalbumin immunoreactive interneurons (P...