Effect of FcRγ deficiency and integrin α_IIbβ₃ and P2Y₁₂ inhibition on occlusive arterial thrombus formation following electrolytic injury. (A) Electrolytic injury was induced in the carotid artery of FcRγ-deficient mice (FcRγ^–/–, n = 5) or wild-type mice treated with vehicle alone (wild-type, n = 5), GPI562 (5 mg/kg) (+ GPI562, n = 5) or clopidogrel (50 mg/kg) (+ clopidogrel, n = 4) as described in “Materials and methods.” Carotid artery blood flow was monitored over a 30-minute time period following arterial injury (indicated by arrows). Error bars are average SEM from repeated measures ANOVA. (B) Total blood flow over a 30-minute period. Error bars are ± 1 SEM. (C) Histologic analysis of carotid arteries from FcRγ^–/– or wild-type mice treated with vehicle alone, GPI562, or clopidogrel. Tissue samples were stained with Castair stain in which platelets stain purple, fibrin stain red, red blood cells stain yellow, and collagen stains blue. Platelet-rich thrombi (PT) are highlighted in wild-type control and FcRγ^–/– mice.