title: Smooth muscle cells from human urinary bladder express connexin 43 in vivo and in vitro.
abstract: Smooth muscle cells (SMC) of the human urinary bladder are believed to be electrically coupled. However, it has not been successfully demonstrated the nature of the underlying cell-cell communication. Here, we used Western blot technique to demonstrate the gap junction protein connexin 43 (Cx 43) in human bladder musculature and in smooth muscle cell cultures. We found expression of Cx 43 in all samples of the detrusor (Mdv, n=6) and in five of six samples of the internal sphincter (Mv). Cx 43 expression was less in cell cultures, 60% showing Cx 43 expression. Iontophoretic application of the gap junction permeable fluorescent dye lucifer yellow revealed a mean of 2.6+/-2.2 (mean+/-SD, n=8) coupled cells in cultured smooth muscle cells. Our findings support the notion that Cx 43 is constitutively expressed in human bladder SMC in vivo. Thus, the function of the bladder is likely to be influenced by the organisation of smooth muscle cells into functional syncytia.
authors.affiliation: Department of Urology, University of Leipzig AöR, Stephanstr. 11, 04103 Leipzig, Germany. neuj@medizin.uni-leipzig.de
authors.forename: Jochen
authors.initials: J
authors.lastname: Neuhaus
authors.forename: Annett
authors.initials: A
authors.lastname: Weimann
authors.forename: Jens-Uwe
authors.initials: JU
authors.lastname: Stolzenburg
authors.forename: Hartwig
authors.initials: H
authors.lastname: Wolburg
authors.forename: Lars-Christian
authors.initials: LC
authors.lastname: Horn
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Dorschner
mesh_terms: D000368:Aged; D015153:Blotting, Western; D018031:Connexin 43 / Q000032:analysis* / Q000502:physiology*; D005260:Female; D017629:Gap Junctions / Q000473:pathology / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D009130:Muscle, Smooth / Q000737:chemistry* / Q000473:pathology / Q000503:physiopathology*; D032389:Myocytes, Smooth Muscle / Q000737:chemistry* / Q000473:pathology / Q000502:physiology*; D001743:Urinary Bladder / Q000737:chemistry* / Q000473:pathology / Q000503:physiopathology*; D001745:Urinary Bladder Diseases / Q000473:pathology / Q000503:physiopathology*
chemical_list: D018031:Connexin 43