Alcohol increases efficacy of immature synapses in a neurosteroid-dependent manner.

Détails

ID Serval
serval:BIB_8F1360093419
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Alcohol increases efficacy of immature synapses in a neurosteroid-dependent manner.
Périodique
The European journal of neuroscience
Auteur(s)
Mameli M., Valenzuela C.F.
ISSN
0953-816X (Print)
ISSN-L
0953-816X
Statut éditorial
Publié
Date de publication
02/2006
Peer-reviewed
Oui
Volume
23
Numéro
3
Pages
835-839
Langue
anglais
Notes
Publication types: Comparative Study ; Journal Article ; Research Support, N.I.H., Extramural
Publication Status: ppublish
Résumé
Fetal ethanol exposure persistently affects hippocampal circuits leading to learning and memory disabilities. Although the mechanisms responsible for these effects are not fully understood, several studies implicate neurosteroids as mediators of the actions of ethanol. A neurosteroid that appears to be critical for the fetal actions of ethanol is pregnenolone sulfate (PREGS). We found that chronic prenatal ethanol exposure increases PREGS levels in the fetal brain and that an endogenous PREGS-like neurosteroid strengthens excitatory transmission in the neonatal hippocampus. Therefore, we hypothesized that ethanol could affect synaptic transmission in the developing hippocampus in a PREGS-dependent manner. We used patch-clamp electrophysiological techniques and found that 50 mm ethanol strengthens AMPA receptor-mediated transmission in the CA1 region by reducing the failure rate of low-efficacy synapses. This effect was age-dependent and was occluded by application of exogenous PREGS. An anti-PREGS antibody scavenger and blockade of PREGS synthesis prevented the effect of ethanol. These data indicate that the deleterious effects of ethanol on hippocampal development are mediated in part by alterations in neurosteroid production, which results in premature stabilization of excitatory synapses.

Mots-clé
Age Factors, Animals, Animals, Newborn, Antibodies/pharmacology, Central Nervous System Depressants/pharmacology, Dose-Response Relationship, Drug, Drug Interactions, Electric Stimulation/methods, Ethanol/pharmacology, Excitatory Postsynaptic Potentials/drug effects, Excitatory Postsynaptic Potentials/physiology, Excitatory Postsynaptic Potentials/radiation effects, Female, Hippocampus/cytology, Hippocampus/growth & development, In Vitro Techniques, Male, Neurons/cytology, Neurons/drug effects, Patch-Clamp Techniques/methods, Pregnancy, Pregnenolone/immunology, Pregnenolone/pharmacology, Rats, Rats, Sprague-Dawley, Synapses/drug effects, Synaptic Transmission/drug effects, Synaptic Transmission/physiology, Tyramine/analogs & derivatives, Tyramine/pharmacology
Pubmed
Web of science
Création de la notice
03/02/2017 12:16
Dernière modification de la notice
03/03/2018 19:20
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