Figure 3
From: Concentric lamellae – novel microanatomical structures in the articular calcified cartilage of mice
Ultrastructural examination of chondrocytes from different zones of cartilage in a 53 week old BALB/c AKU mouse. (a) TEM micrograph of a flattened chondrocyte in the superficial zone of the HAC. Individual collagen fibres, located in the pericellular matrix (PCM), lie parallel to the articular surface (arrowed) (x26,500). Inset: Location of the chondrocyte in HAC (x8250). (b) TEM micrograph of a chondrocyte in the deep zone of the HAC. Specific structures within the cell have been labelled (x9900). (c) TEM micrograph of hypertrophic chondrons in the ACC. Both sets of chondrocytes appeared chondroptotic with chromatin condensation, cellular disintegration and the final stage of chondroptosis, empty lacunae, all present. Concentric lamellae were also visible surrounding the cells (dashed lines). Inset: Location of the chondrocyte in the HAC (arrowed) (x2500). Inset: Location of the cells in the ACC (x2500). Tissue fixed in glutaraldehyde. Scale = (a) 0.5 µm, (b) 2 µm, (c) 5 µm.
