An endogenous adrenoceptor ligand potentiates excitatory synaptic transmission in cultured hippocampal neurons. - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Cerebral Cortex Année : 2001

An endogenous adrenoceptor ligand potentiates excitatory synaptic transmission in cultured hippocampal neurons.

Résumé

Noradrenergic inputs modulate hippocampal function via distinct receptors. In hippocampal neuronal cultures, mRNA expression of adrenoceptor subtypes is maintained from 1 day in vitro (DIV) to 22 DIV. Noradrenaline dose-dependently stimulates phosphoinositide (PI) breakdown in both immature and mature cultures through the activation of alpha1 receptors. At 22 DIV, basal PI breakdown depends on excitatory synaptic activity since it is decreased by tetrodotoxin or glutamate receptor antagonists. At 22 DIV, a similar decrease of basal PI breakdown is also observed with alpha1, alpha2 or beta adrenoceptor antagonists. These effects are not additive with that produced by tetrodotoxin. Adrenergic antagonists also strongly reduce spontaneous excitatory post-synaptic currents (sEPSC) as evidenced by whole cell recording. Therefore, in hippocampal cultures, excitatory transmission is modulated by a tonic activation of adrenoceptors probably produced by an endogenous ligand. Indeed, (i) the depletion of catecholamine pools by reserpine also decreases both basal PI metabolism and sEPSC; (ii) hippocampal neurons possess both tyrosine hydroxylase (TH) and dopamine-beta-hydroxylase mRNAs, encoding enzymes required for catecholamine synthesis; and (iii) some hippocampal neurons show TH-immunoreactivity. TH-positive cells are also detected in E18 hippocampal sections. Thus, cultured hippocampal neurons synthesize and release an adrenergic-like ligand, which tonically potentiates excitatory synaptic transmission in mature cultures.
Fichier principal
Vignette du fichier
1100878.pdf (290.45 Ko) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-00397700 , version 1 (09-06-2021)

Licence

Paternité - Pas d'utilisation commerciale - Pas de modification

Identifiants

Citer

Magali Aubert, Janique Guiramand, Ariane Croce, Gisèle Roch, Alain Szafarczyk, et al.. An endogenous adrenoceptor ligand potentiates excitatory synaptic transmission in cultured hippocampal neurons.. Cerebral Cortex, 2001, 11 (9), pp.878-87. ⟨10.1093/cercor/11.9.878⟩. ⟨hal-00397700⟩
77 Consultations
38 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More