The material properties of hypothermically stored knee condyles progressively decline over 60 days.
Nitric oxide (NO.) is a multifunctional messenger molecule generated by a family of enzymes, collectively termed the nitric oxide synthases. We investigated the role of NO. in the modulation of two metal-dependent proteolytic enzymes (collagenase and stromelysin) which are activated during inflammatory and infective arthritis. The inflammatory mediators interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha) and the bacterial cell wall fragment endotoxin, induced both nitric oxide synthase activity and
Inhibition of interleukin 1 induced chondrocyte protease activity by a corticosteroid and a nonsteroidal antiinflammatory drug
We report that administration of the corticosteroid, methylprednisolone (PRED) inhibited interleukin 1 (IL-1) induction of chondrocyte caseinolytic activity (25-55%) and collagenolytic activity (15-24%). The nonsteroidal antiinflammatory drug (NSAID), naproxen (NAP) had no effect on either enzyme activity over a therapeutic range (7-30 micrograms/ml) but at 120 micrograms/ml inhibited IL-1 induced caseinolytic and collagenolytic activity by 17 and 19%, respectively. However, PRED (2 micrograms/ml) in combination with NAP (30 micrograms/ml) significantly