Figure 2: S1P mobilizes P-selectin in endothelial cells and induces rolling through a S1P3/Gq/PLC/Ca2+ pathway.
From: Sphingosine-1-phosphate receptor 3 promotes leukocyte rolling by mobilizing endothelial P-selectin
(a) HUVECs were stimulated with S1P (1 μM) for 5 min in the presence or absence of the S1P3 inhibitor TY-52156 (10 μM) or stimulated with the S1P1 agonist SEW2871 (1 μM). P-selectin surface expression was analysed using flow cytometry. Data shown are from at least three independent experiments. Representative histogram is shown as inset. (b) HUVECs were stimulated with S1P (1 μM) in the presence or absence of U73122 (3 μM for 2 min) or thapsigargin (3 μM for 5 min) in combination with EGTA (3 mM for the last 1 min). P-selectin was analysed using flow cytometry 5 min after the addition of S1P. Data shown are from at least three independent experiments. (c) Leukocyte rolling was quantified in postcapillary venules of the cremaster muscle of Gq/11−/− mice (Gq endothelial −/−) in the presence (n=4) or absence (n=5) of the S1P3 inhibitor TY-52156 (1.25 mg kg−1 i.p. 30 min before the experiment) and in controls (n=4). P-selectin-blocking antibody was injected to confirm complete dependence of rolling on P-selectin. Quantitative data are presented as mean±s.e.m. Significance was established using a paired two-tailed Student’s t-test or a Kruskal–Wallis analysis of variance (ANOVA) on ranks. *P<0.05; **P<0.01.
