The effects of cyclic mechanical stretch on nuclear protein import in vascular smooth muscle cells

Vascular smooth muscle cells are continuously exposed to cyclic mechanical strain due to changes in blood flow and pressure within the vessel walls. These mechanical stimuli (such as intermittent or turbulent flow and changes in pressure) can stretch the cells and induce significant alterations in cell growth and shape. The cell nucleus plays a central role in the regulation of cell growth and gene expression. The transport of molecules through the nuclear pore complex, a channel linking the cell cytoplasm to the nucleoplasm, is a key pathway through which gene expression in a cell is controlled. Identifying the processes that modulate the flow of signalling molecules through this channel is important information if we are to understand the factors that can regulate cell growth. It is presently unknown if the mitogenic effects associated with mechanical stimuli may occur through changes in nuclear pore morphology and/or its function. The purpose of the present investigation was to determine whether mechanical stretch of the cell in vitro will alter nuclear protein import in vascular smooth muscle cells and the mechanisms that may be responsible for this change in nuclear import. (Abstract shortened by UMI.)...