Figure 5

Effect of chronic cigarette smoke exposure on the protein levels of MMP-12 in lung tissue. Semiquantitative scoring of MMP-12 on immunohistochemical stained lung tissue sections of wild type and NK₁-R^-/- mice upon chronic (24 weeks) exposure to air or cigarette smoke (A). Photomicrograhps of immunohistochemistry for MMP-12 protein on lung tissue of wild type and NK₁-R^-/- mice upon chronic (24 weeks) exposure to air or cigarette smoke (magnification ×400). (B) air-exposed wild type mice, (C) cigarette smoke-exposed wild type mice, (D) air-exposed NK₁-R^-/- mice and (E) cigarette smoke-exposed NK₁-R^-/- mice. Photomicrographs are representative of 8 animals per group.