As ATX produces bioactive lipid LPA through the hydrolysis of LPC, the LPA concentration was measured in mouse blood plasma after ischemia–reperfusion (I/R) for 1.5 h and 24 h, respectively, in all the following groups of mice: sham, I/R (ATXfl/fl with ischemia–reperfusion), and ERT2 ATX−/− (ERT2 ATX−/− with ischemia–reperfusion). This evidence concerns the gene MAPK3 and ischemia.