title: Shear stress increases endothelial platelet-derived growth factor mRNA levels.
abstract: We have investigated the effect of shear stress on platelet-derived growth factor (PDGF) A and B chain mRNA levels in cultured human umbilical vein endothelial cells (hUVEC). The levels of both PDGF A and B mRNA in hUVEC were increased by a physiological shear stress (16 dyn/cm2), reaching a maximum approximately 1.5-2 h after the onset of shear stress and returning almost to control values at 4 h. The peak levels showed a more than 10-fold enhancement for PDGF A mRNA and a 2- to 3-fold increase for PDGF B mRNA (P less than 0.05). PDGF A mRNA also showed a shear-dependent increase from 0 to 6 dyn/cm2 (P less than 0.05) and then plateaued from 6 to 51 dyn/cm2. PDGF B mRNA levels were elevated as shear stress increased from 0 to 6 dyn/cm2 then declined gradually to a minimum at 31 dyn/cm2 (P less than 0.05) and increased again when shear stress rose to 51 dyn/cm2 (P less than 0.05). PDGF, a potent smooth muscle cell mitogen and vasoconstrictor, released from the endothelium may regulate the blood flow in vivo. The shear stress-dependent elevation of PDGF A and B mRNA in endothelial cells may be involved in the adaptation of blood vessels to flow mediated by the endothelium.
authors.affiliation: Department of Chemical Engineering, Pennsylvania State University, University Park 16802.
authors.forename: H J
authors.initials: HJ
authors.lastname: Hsieh
authors.forename: N Q
authors.initials: NQ
authors.lastname: Li
authors.forename: J A
authors.initials: JA
authors.lastname: Frangos
mesh_terms: D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000378:metabolism*; D006801:Humans; D010982:Platelet-Derived Growth Factor / Q000145:classification / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism*; D013314:Stress, Mechanical
chemical_list: D010982:Platelet-Derived Growth Factor; D012333:RNA, Messenger