Platelet deposition on collagen under flow does not require signal transduction through the adaptor LAT. Whole blood from the indicated mice was perfused over collagen-coated glass slides at wall shear rates at and between 400 and 1300 s^–1 for 4 minutes. (A) Surface coverage of LAT-deficient (▪; n = 6) and wild-type (□; n = 3) platelets. The results shown are the mean ± SEM. There is a statistically significant difference between LAT-deficient and wild-type platelets at 1300 s^–1 (P < .05). (B) Representative phase-contrast images after perfusion. The lines seen in the upper left portions of some panels are visual artifact and do not arise due to abnormalities in the collagen-coated surface.