Uncoupling of α- and δ- granule release from GPIIb/IIIa activation in neonates. Characteristics of preterm neonates <32 weeks GA, 32 to 36 weeks GA, >36 weeks GA (t), infants 28d-2a, children 2 to 13a and adults >13a are displayed. Whole blood was preincubated with (A-D) TRAP-6 (5 μM), (E-H) ADP (5 μM), or (I-L) U46619 (2 μM). (A,B,E,F,I,J) CD62P or (C,G,K) CD63 expression or (D,H,L) GPIIb/IIIa activation were assessed flow cytometry. (M-P) Quadrant analysis of CD63 and PAC-1 upon (M,N) TRAP-6, (O) ADP, or (P) U46619 stimulation was performed. Representative curves are shown in panel M. The median ± 95% confidence interval (CI) is displayed in panels A-L. Mean ± 95% CI is shown in panels N-T. Differences were analyzed using the Kruskal-Wallis test. ∗P < .05; ∗∗P < .01; ∗∗∗P < .001; ∗∗∗∗P < .0001. ns, nonsignificant.