All treatment groups (Controls: ○ solid line; IL-1α □ solid line; Load: △ dashed line; Load+ IL-1α ◇ dotted line) were incubated for 24 hours without any treatment, exposed on day 0 (Stimulated) to IL-1α (10 ng/ml), Load (0.2 MPa) and Load+IL-1α for 3 days (days 0–3), and the treatments removed on day 4 (Recovery) for another 6 days (days 4–9). The PG loss to the media per day was normalized to the initial PG content in the explant. All groups had similar initial PG contents at the start of the experiment (day −1, data not shown), and similar PG loss during the 24 hrs prior to treatment (day 0). Load did not affect the IL-1 induced PG catabolism. Data are means ± SEM for n=10 explants.