Effect of 2-(p-hydroxyanilino)-4-(p-chlorophenyl) thiazole (Compound 2) on vasomotor responses of isolated vessels. Basilar and femoral arteries of rat were challenged with cumulative concentrations of 5-hydroxytryptamine (5-HT; A, B), sphingosine-1-phosphate (S1P, C) or phenylephrine (PE, D) following 1h incubation with vehicle (dimethylsulfoxide, 0.1%) or 10 µmol/L Compound 2. Contractile responses are normalized to vasoconstriction induced by exposure to 100 mmol/L KCl in the same preparation before treatment with Compound 2. Data are mean ± SEM of 7–12 independent measurements. In A and C P<0.01; two-way ANOVA.