A microfluidic system for the study of the response of endothelial cells under pressure

Hydrostatic pressure can affect the structure and function of endothelial cells (ECs). A microfluidic system was built to study how ECs respond to applied pressure. The system included a syringe pump, a PDMS-glass microfluidic chip, and a digital manometer for pressure monitoring. The manometer was connected with the chip in two ways (one was before the inlet and the other after the outlet of the microchannel). The static control and flowing control systems were also set up. Human umbilical vein endothelial cells (HUVECs) were cultured in the 4 cm × 2 mm × 100 μm channel. Pressure of 12 ± 0.5 or 18 ± 0.5 kPa was applied on the cells for 8 h. The F-actin cytoskeleton and the nuclei of the cells were stained for examination and endothelin-1 (ET-1) released from the cells in the channel was assayed by ELISA. The results showed that the cell area and ET-1 concentration increased with the pressure and a higher pressure caused more damages to the cells. This microfluidic system provides a convenient and cost-effective platform for the studies of cell response to pressure.