Secretory response of endothelin-1 in cultured human glomerular microvascular endothelial cells to shear stress.
The shear-induced secretory response of endothelin-1 (ET-1) by human microvascular endothelial cells was studied using paired human glomerular microvascular endothelial cell (HGMEC) cultured monolayers exposed to steady-state laminar shear stress for up to 10 hours. The first cell monolayer was subjected to a shear stress of 0.65 N m-2 and the second, 1.3 N m-2. ET-1 secretion was determined by radioimmunoassay. Over 10 hours of shear, the total cumulative secretion of ET-1 was 237.4 pg/cm2 for the monolayer exposed to 1.3 N m-2 and 143.6 pg/cm2 for the monolayer exposed to 0.65 N m-2. The average ET-1 secretion rate was 20.90 +/- 2.15 and 12.45 +/- 1.05 pg/cm2.h at 0.65 N m-2 and 1.3 N m-2, respectively. The results showed that ET-1 secretion varied with the time of shear in a nonlinear fashion. Although the level of shear stress affected the absolute value of ET-1 cumulative secretion and secretion rate, the major secretion period for both monolayers occurred between 2.0 and 8.0 hours, with the peak secretion rate occurring at approximately 5 hours. Thus, the response of cultured human microvascular endothelial cells to shear stress differed from that of large vessel endothelial cell cultures in terms of ET-1 secretion. In addition to the level of shear stress, the time of shear was also an important determinant of ET-1 secretion. Consequently, the heterogeneity of vascular endothelial cells and the time of shear should both be considered in future research on the secretion of vascular endothelial cell cultures.
Wang
G
G
College of Bioengineering, Key Lab for Biomechanics & Tissue Engineering, State Ministry of Education, Chongqing University, Chongqing, China.
Cai
S
S
Deng
X
X
Ouyang
K
K
Xie
G
G
Guidoin
R
R
D002196:Capillaries; D019332:Endothelin-1 / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007678:Kidney Glomerulus / Q000098:blood supply*; D012044:Regression Analysis; D013314:Stress, Mechanical; D014661:Vasoconstriction / Q000502:physiology*
D019332:Endothelin-1