title: Regulation of the endothelin system by shear stress in human endothelial cells.
abstract: In this study, the effect of shear stress on the expression of genes of the human endothelin-1 system was examined. Primary cultures of human umbilical vein endothelial cells (HUVEC) were exposed to laminar shear stress of 1, 15 or 30 dyn cm-2 (i.e. 0.1, 1.5 or 3 N m-2) (venous and two different arterial levels of shear stress) in a cone-and-plate viscometer. Laminar shear stress transiently upregulates preproendothelin-1 (ppET-1) mRNA, reaching its maximum after 30 min (approx 1.7-fold increase). In contrast, long-term application of shear stress (24 h) causes downregulation of ppET-1 mRNA in a dose-dependent manner. Arterial levels of shear stress result in downregulation of endothelin-converting enzyme-1 isoform ECE-1a (predominating in HUVEC) to 36.2 +/- 8.5 %, and isoform ECE-1b mRNA to 72.3 +/- 1.9 % of static control level. The endothelin-1 (ET-1) release is downregulated by laminar shear stress in a dose-dependent manner. This downregulation of ppET-1 mRNA and ET-1 release is not affected by inhibition of protein kinase C (PKC), or tyrosine kinase. Inhibition of endothelial NO synthase (L-NAME, 500 microm) prevents downregulation of ppET-1 mRNA by shear stress. In contrast, increasing degrees of long-term shear stress upregulate endothelin receptor type B (ETB) mRNA by a NO- and PKC-, but not tyrosine kinase-dependent mechanism. In conclusion, our data suggest the downregulation of human endothelin synthesis, and an upregulation of the ETB receptor by long-term arterial laminar shear stress. These effects might contribute to the vasoprotective and anti-arteriosclerotic potential of arterial laminar shear stress.
authors.affiliation: Institute of Pathophysiology, Faculty of Medicine, Martin Luther University Halle-Wittenberg, D-06097 Halle, Germany. henning.morawietz@medizin.uni-halle.de
authors.forename: H
authors.initials: H
authors.lastname: Morawietz
authors.forename: R
authors.initials: R
authors.lastname: Talanow
authors.forename: M
authors.initials: M
authors.lastname: Szibor
authors.forename: U
authors.initials: U
authors.lastname: Rueckschloss
authors.forename: A
authors.initials: A
authors.lastname: Schubert
authors.forename: B
authors.initials: B
authors.lastname: Bartling
authors.forename: D
authors.initials: D
authors.lastname: Darmer
authors.forename: J
authors.initials: J
authors.lastname: Holtz
mesh_terms: D016282:Aspartic Acid Endopeptidases / Q000235:genetics / Q000378:metabolism; D015152:Blotting, Northern; D002478:Cells, Cultured; D019332:Endothelin-1 / Q000235:genetics* / Q000378:metabolism; D000072396:Endothelin-Converting Enzymes; D016232:Endothelins / Q000235:genetics* / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000201:enzymology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D006801:Humans; D008666:Metalloendopeptidases; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D052250:Nitric Oxide Synthase Type III; D019335:Nitroarginine / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D011498:Protein Precursors / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D013314:Stress, Mechanical; D014471:Umbilical Veins / Q000166:cytology
chemical_list: D019332:Endothelin-1; D016232:Endothelins; D004791:Enzyme Inhibitors; D011498:Protein Precursors; D012333:RNA, Messenger; D019335:Nitroarginine; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III; D011493:Protein Kinase C; D016282:Aspartic Acid Endopeptidases; D008666:Metalloendopeptidases; C000606923:ECE1 protein, human; D000072396:Endothelin-Converting Enzymes; D019331:NG-Nitroarginine Methyl Ester