Epileptiform activity generated by endogenous acetylcholine during blockade of GABAergic inhibition in immature and adult rat hippocampus
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Ημερομηνία
Συγγραφείς
Gruslin, E.
Descombes, S.
Psarropoulou, C.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Brain Res
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
We tested the effects of the acetylcholinesterase inhibitor eserine (10 mu M), an indicator of the activity of endogenous ACh, on the generation of epileptiform discharges during blockade of inhibitory GABA(A)-mediated potentials by bicuculline (10 mu M), in the CA3 area of hippocampal slices from postnatal days 4-20 (P4-P20) immature and adult rats. Eserine provoked or significantly increased the frequency of spontaneous synchronous epileptiform discharges, in 6/22 (27%) P4-P10 slices, 34/35 P11-P20 slices and 18/18 adult slices, an epileptogenic effect. Ln immature slices, spontaneous discharges showed a stable frequency throughout perfusion with eserine, while in 5/11 adult slices an initial fast frequency was followed by a slower steady-state one. The cholinergic agonist carbachol (CCh, 25 mu M) provoked only transient or no spontaneous synchronous discharges in adult slices (n = 8), thus suggesting that massive activation of cholinergic receptors may lead to suppression of epileptiform activity in adult brain. Stimulus-induced excitatory CA3 responses, were depressed by eserine in approximately half of 20 P4-P10, 45 P11-P20 and 11 adult slices. The depression consisted of a decrease in the amplitude, duration, and number of population spikes of the field potentials by about 30%, a minor neuroprotective effect, which did not change with maturation. The different developmental profiles of the epileptogenic and neuroprotective effects of endogenous ACh suggest that they are mediated by different mechanisms. These experiments demonstrate that, endogenous aCh is sufficient to induce epileptogenesis during a decrease or failure of GABAergic inhibition, in both greater than or equal to P10 immature and in adult hippocampus. We therefore suggest that clinical or behavioral conditions which raise the concentration of endogenous ACh may lower the threshold to seizures. (C) 1999 Elsevier Science B.V. All rights reserved.
Περιγραφή
Λέξεις-κλειδιά
epilepsy, cholinergic, seizure, eserine, development, ontogenesis, excitatory synaptic transmission, postnatal-development, muscarinic receptors, pyramidal cells, induced epileptogenesis, brain-regions, ca3 area, release, ethanol, estradiol
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000081730400022
http://ac.els-cdn.com/S0006899399016054/1-s2.0-S0006899399016054-main.pdf?_tid=a3675cf4-ad80-11e2-8ec4-00000aacb35f&acdnat=1366878058_d49dce0ff9b30e1dd9825adea0dd21c3
http://ac.els-cdn.com/S0006899399016054/1-s2.0-S0006899399016054-main.pdf?_tid=a3675cf4-ad80-11e2-8ec4-00000aacb35f&acdnat=1366878058_d49dce0ff9b30e1dd9825adea0dd21c3
Γλώσσα
en
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Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Επιστημών και Τεχνολογιών. Τμήμα Βιολογικών Εφαρμογών και Τεχνολογιών