Figure 2.

S1P stimulated vascular relaxation in an endothelium-dependent manner. (A) Concentration–response curves showing the vasorelaxant effect of S1P (1 nM–30 µM) on U46619-pre-contracted endothelium-intact (n= 10) and endothelium-denuded (n= 8) isolated CA and concentration–response curves showing the effect of S1P (1 nM–30 µM, n= 10) in the presence of (B) W146, a selective S1P₁ antagonist (10 µM) (n= 5) (C) JTE013, a selective S1P₂ antagonist (10 µM) (n= 6) and (D) CAY10444, a selective S1P₃ antagonist (10 µM) (n= 5) in rat endothelium-intact U46619-pre-contracted CA. Data are expressed as a % of U46619-induced tone and shown as mean ± SEM for n arteries from different animals. *P < 0.05 versus S1P alone as determined by two-way anova.