Pinealocytes in rats: connexin identification and increase in coupling caused by norepinephrine.
Dye coupling was observed between pinealocytes in acutely dissected pineal glands of adult rats. Pinealocytes maintained in culture were also electrically coupled. Connexins 26 and 43 and their respective mRNAs were present but neither connexin32 nor its mRNA were detected. Pinealocytes expressed only connexin26 whereas connexin43 was confined to astrocytes. In 5-day-old cultures of pinealocytes the incidence of dye coupling and level of immunodetectable connexin26 were low, and both were increased by norepinephrine (NE). The increase in incidence of coupling was maximal at around 6 h after treatment and was prevented by inhibitors of protein or mRNA synthesis. NE-induced metabolic and electrical synchronization mediated by gap junctions may favor melatonin secretion.
Sáez
J C
JC
Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461.
Berthoud
V M
VM
Kadle
R
R
Traub
O
O
Nicholson
B J
BJ
Bennett
M V
MV
Dermietzel
R
R
D000818:Animals; D015152:Blotting, Northern; D002478:Cells, Cultured; D017630:Connexins; D004553:Electric Conductivity; D005260:Female; D007365:Intercellular Junctions / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D008565:Membrane Proteins / Q000032:analysis* / Q000235:genetics; D008839:Microelectrodes; D009638:Norepinephrine / Q000494:pharmacology*; D010750:Phosphoproteins / Q000032:analysis; D010870:Pineal Gland / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains
D017630:Connexins; D008565:Membrane Proteins; D010750:Phosphoproteins; D012333:RNA, Messenger; D009638:Norepinephrine