Atrial PMN infiltration and MPO accumulation was attenuated by CD11b-deficiency.

(A) Number of MPO- and Ly6G-positive leukocytes in atrial sections of WT and CD11b^−/− mice upon vehicle or Ang II treatment was quantified in 4–5 FOVs per atrium (FOV  =  field of view, ×40). *  =  p<0.05, ***  =  p<0.001. (B) Representative images of immunofluorescence staining of PMN in mouse atrial tissue: blue  =  DAPI, red  =  Ly6G, green  =  MPO. Arrowheads indicate leukocytes. Scale bar  = 50 µm. (C, D) Protein expression of ICAM-1 and VCAM-1 in atrial tissue of WT and CD11b^−/− mice upon vehicle or Ang II infusion. Representative immunoblots are shown, where bands are spliced together as they were noncontinuous but were run on the same gel. (E) MPO in atrial tissue of WT and CD11b^−/− mice. *  =  p<0.05, **  =  p<0.01. (F) Amount of MPO deposition in the coronary circulation of WT and CD11b^−/− mice. *  =  p<0.05, **  =  p<0.01.