Elastic fiber degradation in the wild type (WT) and mgR/mgR mice. a) elastin breaks per field under 40x magnification in WT, mgR/mgR, and doxycycline-treated mgR/mgR mice (n=3 aortas/group). *, # p < 0.05 (*relative to wild type controls, # relative to untreated mgR/mgR mice). (b-d) representative trichrome stainings of aortic tissue of WT (b), mgR/mgR (c), and doxycycline-treated mgR/mgR (d) mice at 6 weeks age. Arrows indicates breaks in elastic fibers.