Thrombus formation in FcRγ-null mice and wild-type mice in the FeCl3 and laser-induced thrombosis models. Platelets were labeled by infusion of Alexa 660–conjugated rat anti–mouse CD41 antibody (250 ng/g body weight). (A-B) Injuries were induced with 10% FeCl3 for 5 minutes in wild-type and FcRγ-null mice. (A) The time to the formation of an initial thrombus (WT, n = 12; FcRγ–/–, n = 9). (B) The time to vessel occlusion (WT mice, n = 14; FcRγ–/–, n = 15) are reported and the median times calculated. (C-D) Laser-induced injuries in cremaster arterioles of wild-type and FcRγ-null mice. (C) Median integrated platelet fluorescence intensity for multiple thrombi of each genotype: WT (26 thrombi in 3 mice); FcRγ–/– (16 thrombi in 3 mice). Fluorescence of platelets in arbitrary units is presented as a function of time. (D) For each thrombus formed, the time to the maximum platelet accumulation into the growing thrombus is reported and the calculated median time indicated.
