Protein phosphatase inhibitor-1 (I-1) has been proposed as a regulatory element in the signal transduction cascade that couples postsynaptic calcium influx to long-term changes in synaptic strength. We have evaluated this model using mice lacking I-1. Recordings made in slices prepared from mutant animals and also in anesthetized mutant animals indicated that long-term potentiation (LTP) is def...

Introduction: Previous studies have shown that low frequency stimulation (LFS) has an inhibitory effect on kindling acquisition. However, the mechanism of this effect has not been completely determined. In the present study, the effect of LFS of the perforant path on seizures induced by rapid perforant path kindling was investigated. Methods: Animals were kindled by electrical stimulation of pe...

In one computational model of hippocampal function, the entorhinal cortical input to CA1 is hypothesized to play a key role in the ability of CA1 to decode CA3 recodings. Here, we develop a modification of this CA1 decoder hypothesis that is applicable to several computational theories of hippocampal function, and then we electrophysiologically investigate one assumption of this new hypothesis....

Virtually all CNS synapses display the potential for activity-dependent long-term potentiation (LTP) and/or long-term depression (LTD). Intriguingly, the potential to exhibit LTP or LTD at many central synapses itself is powerfully modulated by previous synaptic activity. This higher-order form of plasticity has been termed metaplasticity. Here, we show that inhibitory autophosphorylation of Ca...

Platelet-activating factor (PAF), a bioactive lipid (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) derived from phospholipase A(2) and other pathways, has been implicated in neural plasticity and memory formation. Long-term potentiation (LTP) can be induced by the application of PAF and blocked by a PAF receptor (PAF-R) inhibitor in the hippocampal CA1 and dentate gyrus. To further investigat...

The epileptic hippocampus has an enhanced propensity for seizure generation, but how spontaneous seizures start is poorly understood. Using whole cell and field-potential recordings, this study explored whether repetitive perforant-path stimulation at physiological frequencies could induce epileptiform bursts in dentate gyrus minislices from rats with kainate-induced epilepsy. Control slices fr...

46 47 The epileptic hippocampus has an enhanced propensity for seizure generation, but how 48 spontaneous seizures start is poorly understood. Using whole-cell and field-potential recordings, 49 this study explored whether repetitive perforant-path stimulation at physiological frequencies 50 could induce epileptiform bursts in dentate gyrus minislices from rats with kainate-induced 51 epilepsy....

The importance of reelin for cortical lamination in the developing CNS is well established, but its role in nerve fiber growth is not well understood. In this study, hippocampal slices were co-cultured with entorhinal slices of GFP mice, in order to compare the growth of the entorhino-hippocampal path in wild type and reeler mice. On day 6, regenerated fibers were seen to navigate from the ento...

Urban, Nathaniel N., Darrell A. Henze, and German BarrioM E T H O D S nuevo. Amplification of perforant-path EPSPs in CA3 pyramidal Transverse hippocampal slices (400–500 mm) were prepared cells by LVA calcium and sodium channels. J. Neurophysiol. 80: from 3to 6-wk-old male Sprague-Dawley rats (Aghajanian and 1558–1561, 1998. The perforant path forms a monosynaptic conRasmussen 1989; Urban and ...