Entorhinal Cortex Lesions Result In Adenosine-Sensitive High Frequency Oscillations In The Hippocampus.

Entorhinal Cortex Lesions Result In Adenosine-Sensitive High Frequency Oscillations In The Hippocampus.
Exp Neurol. 2015 Jun 10;
Authors: Ortiz F, Gutiérrez R
Abstract
Entorhinal cortex (EC) projections to the hippocampus run along the perforant path and activate the hippocampal area CA3 and the dentate gyrus (DG), which, in turn, drives CA3. Because cortical trauma damages the source of inputs to the hippocampus, we hypothesize that such an event can be reflected in immediate alterations of the hippocampal oscillatory activity. We here explore whether acute, localized disruption of EC-EC connectivity is involved in the generation or modulation of high frequency oscillations (HFO) in the hippocampus. We conducted in vitro electrophysiological recordings in CA3 and DG of combined EC-hippocampal transversal slices prepared from intact brains and from brains with a spatially defined, transversal cut of the EC made in situ, 2hours before in vitro recordings commenced. We also determined if pharmacological manipulations of the adenosine system modulated the fast oscillatory activity. EC-hippocampal slices prepared from brains, in which a transversal lesion of the EC was uni- or bilaterally conducted in situ, displayed spontaneous epileptiform events with superimposed ripples (150-250Hz) and fast ripples (>250Hz), whereas those obtained from non-lesioned brains did not have spontaneous HFO. However, in the latter, high frequency stimul...

Source: Experimental Neurology - June 10, 2015 Category: Neurology Authors: Ortiz F, Gutiérrez R Tags: Exp Neurol Source Type: research