Basic fibroblast growth factor expression precedes flow-induced XXXX .

@entity95 @entity56821 @entity292 @entity3960 @entity432 @entity2548
Arteries enlarge in response to increased blood flow, but the molecular signals controlling this enlargement are not well understood. Basic fibroblast growth factor (bFGF) is a potent mitogen for endothelial cells (EC) and @entity3960 ( @entity3960 ) and promotes cellular proliferation and differentiation. In order to determine whether bFGF is expressed in response to increased blood flow in vivo, carotid-jugular @entity2548 ( @entity2548 ) were created in @entity95 . The carotid artery proximal to the @entity292 was harvested after 1, 3, or 7 days and compared to nonoperated, control carotid arteries. Arterial blood flow increased five- to eightfold in all @entity2548 animals and resulted in a significant increase in wall shear stress. The proximal carotid artery arterial diameter was no different from control after 1 and 3 days (2.3 +/- 0. 1 mm) but enlarged to 2.9 +/- 0.1 mm (P < 0.05) after 7 days. RT-PCR revealed early transcription of bFGF mRNA at 1 and 3 days with increased densitometric band ratio (bFGF/ @entity56821 ) at 7 days. Immunohistochemical analysis revealed bFGF protein localization in EC of control arteries as well as @entity2548 arteries at all time points. @entity3960 and adventitia expression of bFGF was absent in controls, minimal at 1 day, and increased after 3 and 7 days in the experimental groups. Western blotting confirmed the presence of bFGF in samples and transmission immunoelectron microscopy confirmed its nuclear localization. Endothelial cells in vivo express bFGF under both normal and elevated flow conditions. Smooth muscle cells, however, do not express bFGF under normal flow conditions but begin to express bFGF after 1 day of high flow with increased expression after 3 and 7 days. Flow-induced @entity432 begins after @entity3960 expression of bFGF. Therefore, bFGF may play a role in @entity432 and adaptive remodeling in response to increased flow.
