Abstract
Vascular endothelium transduces the temporal gradients in shear stress (tau) originating from unsteady blood flow into functional responses. We measured the effects of step-tau and ramp-tau (i.e., t with different temporal shear gradients) on the lipid lateral diffusion coefficient (D) in the apical membranes of confluent cultured bovine aortic endothelial cells by using fluorescence recovery after photobleaching. A step-tau of 10 dynes/cm2 elicited a rapid (5 s) increase of D in the portion of the cell upstream of the nucleus and a concomitant decrease in the downstream portion. A ramp-tau with a rate of 20 dynes/cm2 per min elicited a rapid (5 s) decrease of D in both the upstream and the downstream portions. The mitogen-activated protein kinases (MAPKs) ERK and JNK were activated by step-tau but not by ramping to the same tau level. Benzyl alcohol, which increases D, enhanced the activities of both MAPKs; cholesterol, which reduces D, diminished these activities. We conclude that the lipid bilayer can sense the temporal features of the applied tau with spatial discrimination and that the tau-induced membrane perturbations can be transduced into MAPK activation. These results have implications for understanding the role of t in modulating vascular functions in health and disease.
Original language | English (US) |
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Pages (from-to) | 216-218 |
Number of pages | 3 |
Journal | The FASEB journal : official publication of the Federation of American Societies for Experimental Biology |
Volume | 16 |
Issue number | 2 |
DOIs | |
State | Published - Feb 2002 |
All Science Journal Classification (ASJC) codes
- Biotechnology
- Biochemistry
- Molecular Biology
- Genetics