Morphologic examination of platelets adhering to collagen- or CRP-coated surfaces. (A) Washed platelets suspended in modified Tyrode-HEPES buffer containing apyrase and 2 mM MgCl₂ were exposed to surfaces coated with collagen (top row) or CRP (bottom row). Scanning electron images show wild-type (WT; left panels) and 85α–/– (right panels) platelets after 90 minutes of incubation. Scale bar indicates 1 μm. (B) Frequency analysis of the length of remnant filopodia from wild-type (dotted columns) and p85α–/– (solid columns) platelets (n = 50) adhering to CRP-coated surface after 60 minutes. Analysis was performed using NIH Image software.