Effects of Different Mechanical Stresses on Nitric Oxide Release Influence Cartilage Macrmolecular Genes Expression in Human Osteoarthritic Chondrocytes in Vitro

不同機械應力對關節炎軟骨細胞釋放一氧化氮及軟骨基質蛋白合成之影響

李炫昇(Mel S. Lee) ； 趙恩塏(En-Kai Chao) ； 翁文能(Steve W. N. Ueng) ； 陳昭宇(Chao-Yu Chen) ； 施俊雄(Chun-Hsiung Shih) ； 趙清貴(Chuck C. K. Chao)

《Journal of Orthopaedic Surgery Taiwan》 18卷1期 (2001/03) Pp. 1-6

並列摘要

The mechanisms for the differential response of articular cartilage to mechanical stimuli such as shear stress or hydrostatic pressure remain nuclear. Nitric oxide is implicated as an important mediator in chondrocytes exposed to shear stress. However, the effect of intermittent hydrostatic pressure on the release of nitric oxide from chondrocytes remains unclear. This study investi-gated the responses of osteoarthritic chondrocytes to mechanical stresses by analysis of matrix macromolecule gene expression and nitric oxide levels. Application of shear stress up-regulated nitric oxide release from osteoarthritic chondrocytes. The in creased nitric oxide release was associated with down-reg-ulation of matrix macromolecule gene expression. In contrast to shear stress, intermittent hydrostatic pressure did not increase nitric oxide release but was associated with up-regulaton of matrix macromolecule gene expression. The data presented here demonstrated that shear stress stimulated while intermit-tent hydrostatic pressure did not increase the release of nitric oxide from chon-drocytes. These data suggest that intermittent hydrostatic pressure is beneficial to cartilage and that shear stress is in favor of degeneration as a result of differ-ent effects on the matrix macromolecular gene expression.