Relative VCAM-1 protein expression in different carotid artery regions. (A) Immunofluorescence analyses of VCAM-1 expression within vascular endothelium including primary and secondary antibody controls. Representative images acquired by laser scanning confocal microscopy (400×) showed vWF staining (green) of intact endothelium, VCAM-1 staining (red) and DAPI staining (blue) for cell nuclei. Bar = 100 µm; arrows denote the ECs. (B) Relative quantification of VCAM-1 expression in low and undisturbed (undist) regions by measuring the integrated optical density (IOD) of positive red area normalized to undisturbed flow region of the NS group. Western blot analysis of VCAM-1 in different regions (C) and quantification of protein expression of VCAM-1 relative to ß-actin (D). Data are mean ± SD from six animals from low flow regions from experiments performed in triplicate. *P < 0.05 versus low regions in NS the group. ▲P < 0.05 versus undisturbed regions in the NS group.