Abstract
Extracellular signal-regulated kinase 5 (ERK5) has been reported to regulate endothelial
cell integrity and protect from vascular dysfunction under continuous laminar flow.
However, the effect of flow on ERK5 levels has not been determined. Confluent human
umbilical vein endothelial cells (HUVECs) were seeded on fibronectin coated glass
slides and serum starved for 2 hours with 1% fetal bovine serum (FBS). HUVECs were
then exposed to to and fro flow (TFF), pulsatile forward flow (PFF), or continuous
laminar flow (CLF) in a parallel plate flow chamber for up to 2 hours. At the end
of experiment, cell lysates were prepared and immunoblotted with antibodies to total
ERK5. Both CLF and TFF exhibited a decrease in ERK5 after levels after 2-hour exposure.
However, the level of ERK5 for PFF remained the same. Disturbed, but not uniform pulsatile,
flow decreases ERK5 levels in HUVECs.
Keywords
pulsatile uniform flow - atherosclerosis - HUVECs - ERK5 - disturbed flow - laminar
flow - uniform flow