Proteoglycan clearance in rat femoral cartilage exposed to 6 aTa

Sprague-Dawley rats were exposed to air at 6 ATA. The decompression time was varied from 30 s to 6 h, resulting in a total pressure time interval from 0--24 h. The amount of rat femoral cartilage proteoglycans was determined by measuring the uronic acid content of the cartilage after papain digestion. The amount of proteoglycans decreased linearly with time of total pressure (decompression time included). No correlation with decompression time was found. It is discussed whether the clearance of proteoglycans is because of a decreased cellular synthesis, assuming the chondrocytes maintain an unchanged degradation activity, or because of an enhanced extracellular transport facilitated by the high pressure.