Abstract: | We studied the production and the effect of nitric oxide (NO) in articular cartilage from rabbits of various ages. 40 New Zealand white rabbits in 4 age groups (1 month, 6 months, 1 year, and 3 years of age with 10 rabbits in each group) were used. Basal and induced levels of NO were lower in cultured chondrocytes from older rabbits. Exogenous NO administration suppressed the proliferative activity of chondrocytes to a greater degree in younger rabbits. Immunohistochemistry showed that older rabbits had fewer eNOS positive chondrocytes. Our findings imply that the age-related change in NO in articular cartilage does not have a relevance to increased NO production in osteoarthrosis. |