Fig. 4.

Accumulation of hypertrophic cartilage in Runx2^HC/HC mice is associated with decreased expression of matrix metalloproteinase. (A) Representative images of alcian blue stained whole tibia from 3-days old littermates. (B) The boxed region is shown at 10x magnification. Double headed arrows indicate the length of hypertrophic cartilage. Scale bar: 200 μm. (C) The length of hypertrophic cartilage measured from the start of the hypertrophic zone to the end of cartilage remnant in littermates (n = 4) is presented in a box and whisker plot. (D, E) RNA isolated from the enzymatically cleared distal femur and proximal tibia epiphyseal growth plates from Runx2^+/+ and Runx2^HC/HC littermates (n = 5) subjected to qPCR. Relative expression of Acan, Mmp9, Mmp13, Adamts4, Adamts5, Timp1, Timp2 and Timp3 normalized with Gapdh is shown in the box and whisker plot. (*P < 0.05, **P < 0.01, ***P < 0.001). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)