Platelet number in (a) mice (n = 5–8) and (b) rats (n = 5–10) at 3, 15, 30, and 60 minutes, and on the 35th day after the administration of unfractionated heparin (UFH) and protamine sulfate (PS). The results are expressed as a percentage of the control samples, and are shown as a median (line) with the interquartile range (box), and maximum and minimum values (whiskers). The number of platelets in the vehicle-treated groups was 617 (565–675) at 3 and 15 minutes, 705 (670–752) at 60 minutes, and 427 (326–467) on the 35th day in the mice. In the rats, the control values were 446 (176–754), 725 (372–746), 668 (196–781), and 637 (494–660) at 15, 30, and 60 minutes, and on the 35th day, respectively. * p < 0.05; ** p < 0.01 vs. vehicle group; Kruskal–Wallis analysis of variance (ANOVA) with Dunn’s post-hoc test.