GENE-REGULATION BY MECHANICAL FORCES

Endothelial cells are subjected to various mechanical forces in vivo f rom the flow of blood across the luminal surface of the blood vessel. The purpose of this review was to examine the data available on how th ese mechanical forces, in particular cyclic strain, affect the express ion and regulation of endothelial cell function. Studies from various investigators using models of cyclic strain in vitro have shown that v arious vasoactive mediators such as nitric oxide and prostacyclin are induced by the effect of mechanical deformation, and that the expressi on of these mediators may be regulated at the transcription level by m echanical forces. There also seems to be emerging evidence that endoth elial cells may also act as mechanotransducers, whereby the transmissi on of external forces induces various cytoskeletal changes and second messenger cascades. Furthermore, it seems these forces may act on spec ific response elements of promoter genes.