CalDAG-GEFI–deficient mice show a similar bleeding time but a reduced amount of blood loss compared with clopidogrel-treated WT mice. (A) Tail-bleeding time in WT (circle, n = 14), clopidogrel-treated WT (WT + clop., triangle, n = 20), CalDAG-GEFI−/− (KO, square, n = 25), and platelet-depleted mice (WT plt. dep., diamond, n = 10). Three independent experiments. (B) Blood volume lost from the severed tails. Each dot represents the bleeding time or blood loss volume determined in individual mice.