Platelet aggregation induced by LPA in whole blood anticoagulated with citrate. (A) Time-course of platelet aggregation induced by 1-acyl-LPA (16:0) in LPA-sensitive donors. Values are mean ± SD, n = 7. (B) Dose-response curves comparing the effect of 1-alkyl-LPA (16:0) and 1-acyl-LPA (16:0) in inducing platelet aggregation in anticoagulated whole blood. Platelet aggregation was measured 5 minutes after addition of LPA. Values represent mean ± SD, n = 4.