Fig. 3. Perioperative changes in the geometric mean fluorescence intensity ratio of phosphorylated and total platelet p38 mitogen-activated protein kinase (MAPK), extracellular signal–regulated kinase (ERK) 1/2, and Akt. Perioperative increase in phosphorylation of intraplatelet p38 MAPK (  A ), ERK1/2 (  B ), and Akt (  C ) was attenuated in the milrinone-treated group [Mil(+)] compared with the group not treated with milrinone [Mil(−)]. These differences between the groups were exaggerated in activated (P-selectin positive) platelets (  D ,  F , and  H ). Data are shown as geometric mean fluorescence intensity values (mean ± SD, n = 17/group).  Open bars = Mil(−) group;  solid bars = Mil(+) group. *  P < 0.01 compared with baseline (0 h) in each group. ¶  P < 0.05 compared with baseline (0 h) in each group. †  P < 0.01 compared with Mil(−) at each time point. §  P < 0.05 compared with Mil(−) at each time point. Representative flow cytometric histograms of P-selectin positive platelets at 2.5 h after the commencement of surgery in the two groups are shown on the  right (  E ,  G , and  I ).  Thin line = Mil(−) group;  bold line = Mil(+) group .