Cyclic mechanical stretch induces VEGF and FGF-2 expression in pulmonary vascular smooth muscle cells.
Vascular endothelial growth factor (VEGF) and basic (b) fibroblast growth factor (FGF-2/bFGF) are involved in vascular development and angiogenesis. Pulmonary artery smooth muscle cells express VEGF and FGF-2 and are subjected to mechanical forces during pulsatile blood flow. The effect of stretch on growth factor expression in these cells is not well characterized. We investigated the effect of cyclic stretch on the expression of VEGF and FGF-2 in ovine pulmonary artery smooth muscle cells. Primary confluent cells from 6-wk-old lambs were cultured on flexible silicon membranes and subjected to cyclic biaxial stretch (1 Hz; 5-25% stretch; 4-48 h). Nonstretched cells served as controls. Expression of VEGF and FGF-2 was determined by Northern blot analysis. Cyclic stretch induced expression of both VEGF and FGF-2 mRNA in a time- and amplitude-dependent manner. Maximum expression was found at 24 h and 15% stretch (VEGF: 1.8-fold; FGF-2: 1.9-fold). These results demonstrate that mechanical stretch regulates VEGF and FGF-2 gene expression, which could play a role in pulmonary vascular development or in postnatal pulmonary artery function or disease.
Quinn
Timothy P
TP
Department of Pediatrics, University of California San Francisco, San Francisco, California 94143, USA. tpquinn@itsa.ucsf.edu
Schlueter
Marielle
M
Soifer
Scott J
SJ
Gutierrez
Jorge A
JA
D000818:Animals; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D002908:Chronic Disease; D016228:Endothelial Growth Factors / Q000032:analysis / Q000235:genetics*; D016222:Fibroblast Growth Factor 2 / Q000032:analysis / Q000235:genetics*; D015870:Gene Expression / Q000502:physiology; D006976:Hypertension, Pulmonary / Q000503:physiopathology; D008222:Lymphokines / Q000032:analysis / Q000235:genetics*; D018485:Muscle Fibers, Skeletal / Q000737:chemistry / Q000502:physiology; D009131:Muscle, Smooth, Vascular / Q000737:chemistry / Q000166:cytology / Q000502:physiology*; D011651:Pulmonary Artery / Q000166:cytology; D012333:RNA, Messenger / Q000032:analysis; D012756:Sheep; D013314:Stress, Mechanical; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D016228:Endothelial Growth Factors; D008222:Lymphokines; D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D016222:Fibroblast Growth Factor 2