Figure 2

JNK-deficient lungs have increased elastin content. (A) PND14 wild type lungs had the typical discrete elastin bands (purple) at the tips of secondary alveolar septa with very little elastin within the tissue (yellow) of the alveolar walls and bases. Scale Bar = 50 μm. (B-C) Grossly, PND14 JNK1^−/− and JNK2%3^−/− lungs had increased quantities of dense elastin (DE) and more diffuse elastin (Dif) throughout the lung. T = Non-elastin tissue, AS = airspace. (D-G) The JNK2%3^−/− lung section is used to demonstrate elastin quantification. The image was separated into dense elastin, diffuse elastin, non-elastin tissue, and airspace components. The pixel counts for each separated image were used for quatitation. (H) Adding the dense and diffuse elastin pixel counts and normalizing to total tissue pixel count, the lungs of JNK1^−/− and JNK2%3^−/− mice had more total elastin than wild type lung. (I) The lungs of JNK2%3^−/− mice had a higher dense elastin to tissue ratio than wild type. (J) The lungs of JNK2%3^−/− mice had increased diffuse elastin content compared to wild type. For image analysis, six animals from two different litters were used for analysis except JNK1^−/− which contained 3 animals from 3 different litters. (K) Western blot for tropoelastin using PND14 lung homogenates from four mice from two different litters demonstrated increased tropoelastin in JNK2%3^−/− mouse lungs. *p < 0.05, **p < 0.01 by one-way ANOVA.