The protein constituents of gap junctions, connexins, have a rapid basal rate of degradation even after transport to the cell surface. We have used cell surface biotinylation to label gap junction-unassembled plasma membrane pools of connexin43 (Cx43) and show that their degradation is inhibited by mild hyperthermia, oxidative stress, and proteasome inhibitors. Cytosolic stress does not perturb...

Remodeling of myocyte interconnections may be an important determinant of ventricular tachycardia in regions bordering healed infarcts. We used quantitative electron microscopy to characterize the distribution of gap junctions in 10 canine left ventricles 3-10 wk after coronary occlusion. In three normal canine left ventricles analyzed ultrastructurally, myocardial gap junctions were distribute...

In order to elucidate the role of gap junctions in adrenal cell responses, we measured the effect of inhibiting gap junctions with 18-alpha glycerrhetinic acid (GA; a potent inhibitor of cell-cell communication) and connexin antisense transfection on cell proliferation and adrenocorticotropin (ACTH)-stimulated steroidogenesis. In these experiments we utilized a bovine adrenocortical cell (SBAC)...

BACKGROUND AND OBJECTIVE Cisplatin is a standard first-line chemotherapeutic agents for treating advanced non-small cell lung cancer. Unfortunately, the clinical application cisplatin is restricted because it induces serious adverse reaction. The aim of this study is to investigate the influence and probable mechanism of berberine on cisplatin antineoplastic effect on lung cancer A549 cells. ...

Neuronal gap junctions are ubiquitous in the brain, but their precise positions in actual neuronal circuits have been uncertain, and their functional roles remain unclear. In this study, I visualized connexin36-immunoreactive gap junctions and examined the structural features of the interconnected dendrites arising from parvalbumin (PV)-positive interneurons in layer 4 of the feline visual cort...

OBJECTIVE The effect of bilirubin on renal pathophysiology is controversial. This study aimed to observe the effects of bilirubin on the proliferation of normal rat renal tubular epithelial cell line (NRK52E) and its potential interplay with gap junction function. METHODS Cultured NRK52E cells, seeded respectively at high- or low- densities, were treated with varying concentrations of bilirub...

Communication through gap junction channels is essential for synchronized and coordinated cellular activities. The gap junction channel pore size, its switch control for opening/closing, and the modulations by chemicals can be different depending on the connexin subtypes that compose the channel. Recent structural and functional studies provide compelling evidence that the amino terminal (NT) d...

BACKGROUND The gap junction plays an important role in spreading of apoptotic and necrotic signals from injured and stressed cells to the neighboring viable cells. The present study was performed to investigate the important role of gap junction communication on rabbits' explosive brain injury. METHODS Explosion of paper detonators was used to create explosive brain injury model in 60 rabbits...

Gap junction channels are composed of members of a multi-gene family of proteins called connexins. These proteins are named by the abbreviation Cx followed by the molecular weight of the specific protein. Mammalian cardiac myocytes express Cx43, Cx45, and Cx40, the former being the major cardiac gap junction protein, which is expressed in atrial and ventricular myocytes as well as in selected r...

Connexin 43 (Cx43) is a gap junction protein whose function in the development of breast cancer and in breast cancer progression remains unclear. Evidence suggests that Cx43 (GJA1) mRNA and protein expression is altered in breast tumors. However, reports indicate both increased and decreased Cx43 levels in human breast cancer samples. Studies also suggest that loss of Cx43 regulated gap junctio...