title: Endothelin receptor B-mediated induction of c-jun and AP-1 in response to shear stress in human endothelial cells.
abstract: In vivo, endothelial cells are constantly exposed to shear stress by flowing blood. Short-term exposure of endothelial cells to shear stress has been shown to induce endothelin-1 release. It is currently unknown, however, whether this shear stress-dependent endothelin-1 release affects the expression and activity of transcription factors. In this study, primary cultures of human endothelial cells from the umbilical vein were exposed to laminar shear stress in a cone-and-plate viscometer. Laminar shear stress for 30 min induced a 2-fold increase in mRNA expression of c-jun , but not c-fos, in human endothelial cells. Blockade of endothelin receptor subtype B (ET B) with BQ788 prevented this shear stress-dependent induction of c-jun expression. The induction of c-jun by shear stress involved protein kinase C and endothelial NO synthase. In addition, exposure of endothelial cells to arterial laminar shear stress for 1 h increased the binding of transcription factor AP-1 to its consensus sequence by 1.7-fold in electrophoretic mobility shift assays. This induction was also mediated by an ET B-dependent pathway. Supershift analysis supports an AP-1 complex containing c-jun, but not c-fos, in human endothelial cells. In conclusion, our data suggest endothelin-1-mediated induction of c-jun expression and activation of AP-1 (possibly as a c-jun homodimer) by laminar shear stress in human endothelial cells.
authors.affiliation: Department of Vascular Endothelium and Microcirculation, Medical Clinic and Policlinic III, University of Technology Dresden, Fetscherstr. 74, Dresden, Germany. Henning.Morawietz@tu-dresden.de
authors.forename: H
authors.initials: H
authors.lastname: Morawietz
authors.forename: A H
authors.initials: AH
authors.lastname: Wagner
authors.forename: M
authors.initials: M
authors.lastname: Hecker
authors.forename: W
authors.initials: W
authors.lastname: Goettsch