Matrix metalloproteinase-9 contributes to parenchymal hemorrhage and necrosis in the remnant liver after extended hepatectomy in mice

Figure 7 Immunohistochemical analysis of accumulated neutrophils with myeloperoxidase staining in remnant livers of wild-type, matrix metalloproteinase-9(-/-), and tissue inhibitors of metalloproteinases-1(-/-) mice at 6 h after 80%-partial hepatectomy. Representative images of myeloperoxidase staining, labeled in green (Alexa Fluor 488), of cytoplasmic azurophilic granules in neutrophils (arrows) in wild-type (WT) mice in remnant liver sections in (A) WT, (B) matrix metalloproteinase (MMP)-9(-/-), and (C) tissue inhibitors of metalloproteinases (TIMP)-1(-/-) mice. A histogram shows the number of accumulated neutrophils in the remnant liver (D). Significantly fewer neutrophils were observed in the remnant liver in MMP-9(-/-) mice than in WT and TIMP-1(-/-) mice (^aP < 0.05, ^bP < 0.01).