Figure 1From: Serum keratan sulfate transiently increases in the early stage of osteoarthritis during strenuous running of rats: protective effect of intraarticular hyaluronan injectionMethod for rat strenuous running. (a) Rodent treadmill machine designed to compulsively make rats run. (b) Protocol for running exercise. Rats were forced to run 30 km in 6 weeks. For the hyaluronan group, the injection was performed initially at 5 days, followed by every 7 days (arrows).Back to article page