Fig. 4. Mmp14 expression is reduced in neonatal (P0) transgenic parietal bone and cartilage. (A,B) Immunohistochemistry for Mmp14. Scale bars: 50 µm. (C,D) Mmp14 mRNA detected by in situ hybridization. Scale bars: 50 µm. (E,F) Areas of cartilage removal in wild-type (E) and transgenic animals (F). The arrows in E indicate areas of proteoglycan depletion and cartilage matrix degradation. Arrows in F denote the corresponding position in transgenic mice. Toluidine Blue staining. Scale bars: 50 µm. (G,H) TUNEL staining. Arrows indicate apoptotic cells. Scale bars: 50 µm. (I,J) Immunohistochemistry staining for HSD2. Scale bars: 100 µm. (K) mRNA expression for Col2a1 and Mmp14 in parietal bone. Parietal bones were dissected by cutting skull bones along coronal and lambdoid sutures. RNA was isolated from the parietal bones of wild-type and transgenic mice. Real-time PCR quantitation of relative mRNA expression levels for Col2a1 and Mmp14 after normalization by 18S expression. Data are represented as mean±s.e.m., n=6. (L) Quantitation of apoptotic chondrocytes in the parietal cartilages of wild type (WT) and Col2.3-11βHSD2 transgenic (tg) mice. Data are represented as mean±s.e.m., n=5.