Modulation of pineal melatonin synthesis by glutamate involves paracrine interactions between pinealocytes and astrocytes through NF-κB activation.
Biomed Res Int
; 2013: 618432, 2013.
Article
en En
| MEDLINE
| ID: mdl-23984387
ABSTRACT
The glutamatergic modulation of melatonin synthesis is well known, along with the importance of astrocytes in mediating glutamatergic signaling in the central nervous system. Pinealocytes and astrocytes are the main cell types in the pineal gland. The objective of this work was to investigate the interactions between astrocytes and pinealocytes as a part of the glutamate inhibitory effect on melatonin synthesis. Rat pinealocytes isolated or in coculture with astrocytes were incubated with glutamate in the presence of norepinephrine, and the melatonin content, was quantified. The expression of glutamate receptors, the intracellular calcium content and the NF- κ B activation were analyzed in astrocytes and pinealocytes. TNF- α 's possible mediation of the effect of glutamate was also investigated. The results showed that glutamate's inhibitory effect on melatonin synthesis involves interactions between astrocytes and pinealocytes, possibly through the release of TNF- α . Moreover, the activation of the astrocytic NF- κ B seems to be a necessary step. In astrocytes and pinealocytes, AMPA, NMDA, and group I metabotropic glutamate receptors were observed, as well as the intracellular calcium elevation. In conclusion, there is evidence that the modulation of melatonin synthesis by glutamate involves paracrine interactions between pinealocytes and astrocytes through the activation of the astrocytic NF- κ B transcription factor and possibly by subsequent TNF- α release.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Glándula Pineal
/
Astrocitos
/
FN-kappa B
/
Ácido Glutámico
/
Comunicación Paracrina
/
Melatonina
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
Biomed Res Int
Año:
2013
Tipo del documento:
Article
País de afiliación:
Brasil