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Fig. 8. Mechanical stimulation in secondary chondrogenesis. (A-F) e14, (G-H) e11.
(A) BrdU labelled at 0 hours, with a 24-hour chase with mechanical
stimulation; labelled doublets are observed. (B) osteocalcin
(ocn) expression in an adjacent section: ocn is not seen
around the SCs (black arrow). (C) BrdU labelled at 0 hours, with a 24-hour
chase without mechanical stimulation; again labelled doublets are found. (D)
Upregulation of ocn expression around the SCs on an adjacent section
(black arrow). (E) BrdU labelled at 16 hours followed by 24-hour chase without
mechanical stimulation; labelled cells are found in the germinal region. (F)
As E, but with mechanical stimulation; BrdU labelled cells are found in the
chondrocyte zone (circled). (G) e11 BrdU pulse at 0 hours followed by a chase
for 48 hours without mechanical stimulation, both chondrocytes (blue circle)
and osteoblasts (red circle) are labelled. (H) Adjacent section to G, showing
ocn expression in BrdU-labelled cells. Scale bars: E, 100 µm; F,
50 µm.