Gap junctions in the chicken pineal gland

Berthoud VM.; Hall, DH; Strahsburger, E; Beyer, EC; Sáez JC


The chicken pineal gland, which contains a heterogeneous cell population, sustains a circadian rhythm of activity. Synchronization of cellular activity of heterogeneous cells might be facilitated by gap junctional intercellular channels which are permeable to ions and second messengers. To test this possibility, we looked for morphologically identifiable gap junctions between the different pineal cells, used antibodies and cDNA probes to screen for the presence of connexins, and tested for functional intercellular coupling. By transmission electron microscopy and immunocytochemistry, gap junctions and connexins were observed between pinealocyte cell bodies, stromal cells, astrocytes, and astrocyte and pinealocyte processes. Two gap junctional proteins, connexin43 and connexin45, were detected by immunocytochemistry, immunoblotting and RNA blot analysis. Functional intercellular coupling was observed in the gland by transfer of low molecular weight dyes. Dye transferred between homologous and heterologous cells. These data suggest that homologous and heterologous gap junctions may provide a mechanism for coordination of the cellular responses of the elements of the biological clock which are induced by lighting cues to produce the circadian rhythm of pineal activity. (C) 2000 Elsevier Science B.V. All rights reserved.

Más información

Título según WOS: Gap junctions in the chicken pineal gland
Título según SCOPUS: Gap junctions in the chicken pineal gland
Título de la Revista: BRAIN RESEARCH
Volumen: 861
Número: 2
Fecha de publicación: 2000
Página de inicio: 257
Página final: 270
Idioma: English