Developmental exposure to polychlorinated biphenyls (PCBs) has been associated with cognitive deficits in children. Rodent studies have revealed impairments in learning tasks involving the hippocampus. The present study sought to examine hippocampal synaptic plasticity in the dentate gyrus and spatial learning in animals exposed to PCBs early in development. Pregnant Long-Evans rats were admini...

Addiction is a major problem of society. The existing evidences have shown that parental addiction impairs CNS development, learning, and memory. With respect to the role of glutamate in dentate gyrus on learning and memory, in this study, the effect of parental addiction to morphine on extracellular glutamate concentration in dentate gyrus was evaluated. For this purpose, male and female rats ...

Dentate spikes (DSs) are positive-going field potential transients that occur intermittently in the hilar region of the dentate gyrus during alert wakefulness and slow-wave sleep. The function of dentate spikes is unknown; they have been suggested to be triggered by perforant path input and are associated with firing of hilar interneurons and inhibition of CA3 pyramidal cells. Here we investiga...

The data reported in Nicolle et al. [30] suggest a preservation of three hippocampal synaptic proteins (synaptophysin, synaptotagmin, and synaptosomal associated protein-25) in old, memory-deficient rats. These are interesting and important data, which, at first consideration, seem to raise a question about whether alterations of synaptic connectivity can contribute in a substantial way to the ...

Because granule cells in the dentate gyrus provide a major synaptic input to pyramidal neurons in the CA3 region of the hippocampus, spike generation by granule cells is likely to have a significant role in hippocampal information processing. Granule cells normally fire in a single-spike mode even when inhibition is blocked and provide single-spike output to CA3 when afferent activity convergin...

We have investigated the propagation of epileptiform discharges induced by 4-aminopyridine (4-AP, 50 microM) in adult mouse hippocampus-entorhinal cortex slices, before and after Schaffer collateral cut. 4-AP application induced 1) ictal epileptiform activity that disappeared over time and 2) interictal epileptiform discharges, which continued throughout the experiment. Using simultaneous field...