Fig. 3

Histological changes in cartilage and Mankin scores. a In the control group, the cartilage was not degenerated and its surface was smooth. In the collagenase-injected group, the loss of cartilage had extended to the radial zone, cell cloning of chondrocytes and reduced stain ability were apparent in the radial zone. In the Torin 1-treated group, the loss of cartilage had only extended to the transitional zone, disappearance of cells in the transitional zone, cell cloning in the radial zone and reduced stain ability were observed. But in the 3-MA-treated group, much more clefts and loss of cartilage and seriously reduced stain ability were seen in the radial zone. b The scores of the collagenase-injected group were higher than those of the control group, and the scores were lower in the Torin 1-treated group but higher in the 3-MA-treated group when compared with collagenase-injected group. n = 10 for each group. ***P < 0.001 (Magnification, 100×)