Figure 1  .

The effects of insulin-like growth factor 1 (IGF1) on the release of collagen fragments induced by interleukin 1α (IL1α) and IL1α + oncostatin M (OSM). Bovine nasal cartilage was cultured in serum-free medium in the presence of either medium alone, or medium containing IL1α (1 ng/ml), IL1α (0.2 ng/ml) + OSM (2 ng/ml) with IGF1 (1-1000 ng/ml) for 14 days. Media were collected at days 7 and 14. The levels of collagen fragments released into the media on days 7 and 14 were determined by the measurement of hydroxyproline as described in "Material and methods". Results shown are for the cumulative collagen release for 14 days of culture and expressed as a percentage of the total (mean (SD)). All assays were done in quadruplicate. The experiments were performed in duplicate. Significance was analysed with respect to the cytokine compared with the cytokine + IGF1, or IGF1 compared with control. *p<0.05, **p<0.01, ***p<0.001 using t test.