Characterization of gap junctions between cultured leptomeningeal cells.
Leptomeningeal cells in intact meninges or dissociated and cultured for 2 h to several weeks were dye-coupled (Lucifer yellow), and voltage-clamped pairs of freshly dissociated leptomeningeal cells were well coupled electrically. Unitary conductances of junctional channels were predominantly 40-90 pS. Junctional conductance was reversibly reduced by 2 mM halothane, 1 mM heptanol and 100% CO2 and was increased by 1 mM 8 Br-cAMP. Two gap junction proteins, connexin 26 and connexin 43, were identified between leptomeningeal cells using immunocytochemical methods; Northern blot analyses of RNA isolated from cultured leptomeningeal cells showed specific hybridization to cDNAs encoding connexins 26 and 43, but not to a cDNA encoding connexin 32. These studies demonstrate co-expression of two connexins in a single cell type in the nervous system; biophysical properties do not differ significantly from those of astrocytes and cardiac myocytes, which express only connexin 43.
Spray
D C
DC
Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461.
Moreno
A P
AP
Kessler
J A
JA
Dermietzel
R
R
D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000438:Alcohols / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D001099:Arachnoid / Q000502:physiology*; D015152:Blotting, Northern; D002478:Cells, Cultured; D017630:Connexins; D004553:Electric Conductivity / Q000187:drug effects; D004594:Electrophysiology / Q000379:methods; D006221:Halothane / Q000494:pharmacology; D007365:Intercellular Junctions / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D008565:Membrane Proteins / Q000032:analysis; D010841:Pia Mater / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics / Q000302:isolation & purification; D051381:Rats; D011919:Rats, Inbred Strains
D000438:Alcohols; D017630:Connexins; D008565:Membrane Proteins; D012333:RNA, Messenger; D015124:8-Bromo Cyclic Adenosine Monophosphate; D006221:Halothane