Hypertrophic chondrocytes contained the highest numerical abundance of peroxisomes compared to proliferative chondrocytes as examples for endochondral ossification.

(A-H) Immunofluorescence stainings of the peroxisomal membrane and matrix proteins PEX14 (A, B, G), catalase (C, D, H) and ABCD3 (E, F) were performed in paraffin-sections from the cartilage (A-D: vertebrae; E, F: femur growth plate; G, H: ribs) of 40-day (A-F) and P0.5 newborn (G, H) mice. Nuclei were stained with Hoechst 33342 (Hoechst) or TOTO-3-iodide (TOTO-3); ALP immunoreactivity (B, D) was used as a marker for skeletal tissue. HC = hypertrophic chondrocytes.