The effect of flow on the neutrophil-mediated Ca2+ responses in human vascular endothelial cells stimulated by endotoxin.
Leukocyte-vascular endothelial cell (EC) interactions which promote inflammatory and immune reactions involve bidirectional signaling between two cell types. We investigated the effects of flow on neutrophil-mediated changes in endothelial intracellular Ca2+ levels ([Ca2+]i). Cultured human umbilical vein ECs stimulated by endotoxin were labeled with Fura-2 and exposed to fluid flow with neutrophils. The individual changes in [Ca2+]i were monitored. The application of flow with neutrophils to stimulated ECs led to an increase in [Ca2+]i although either flow without neutrophils or neutrophils without flow rarely induced a rise in [Ca2+]i. Furthermore, flow application with neutrophils to unstimulated ECs also rarely promoted a rise in [Ca2+]i. These findings suggest that the flow might thus induce or enhance the inflammatory process by the induction of Ca2+ signaling in endotoxin-stimulated endothelium facing neutrophils in the blood flow.
Yamaguchi
M
M
Department of Surgery, Showa University Fujigaoka Hospital, Yokohama, Japan.
Machida
H
H
Korenaga
R
R
Toyama-Sorimachi
N
N
Ando
J
J
Miyasaka
M
M
Matsumoto
T
T
Nakano
H
H
Kumada
K
K
Takeda
M
M
D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling / Q000502:physiology*; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology* / Q000187:drug effects; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D009504:Neutrophils / Q000502:physiology*
D008070:Lipopolysaccharides; D002118:Calcium