Application Experiments Of The Recommended Dose Of Aminoguanidine On INOs Induced The NO Downstream Product

Osteoarthritis was a chronic and degenerative disease occurring in articular cartilage.This disease occured more commonly.Although the etiology of osteoarthritis had still not clear, but it had been confirmed that nitric oxide plays an important role in the development and progression of osteoarthritis.Nitric Oxide inhibited the proliferation of cartilage cells and synthesis of the proteoglycans and the collagen Ⅱ.Nitric Oxide could promote apoptosis of cartilage cells and stimulate cartilage cells the secretion of inflammatory cytokines.Inducible Nitric Oxide Synthase stimulated cartilage cells produced the Nitric Oxide in Osteoarthritis process.Aminoguanidine was a selective inhibitor of Inducible Nitric Oxide Synthase.In this study, aminoguanidine was used as interfering factors to study the expression of inflammatory cytokines associated with osteoarthritis.We detected the Inflammatory factors secreted by the chondrocytes after the chondrocytes were dealed with aminoguanidine.We could understand the way how aminoguanidine effected on osteoarthritis and provide a new way for effective treatment of osteoarthritis.The experimental scheme was divided in vivo and in vitro experiments.In vivo experiment: 30 weighing between 250 g-300 g of Sprague-Dawley rats were randomly divided into control group, model group and injection aminoguanidine group.The control group and the model group were injected saline in intraperitoneal at the fourth week, and the injection aminoguanidine group was injected with aminoguanidine, at a dose of 100 mg/kg, continuous injection for 14 days.Three groups of SD rats were killed by cervical dislocation method,extracting the protein of right knee cartilage tissue and protein concentration was determined.We also detected the vitality of inducible nitric oxide synthase,the content of nitric oxid and the concentration of matrix metalloproteinase-3 and matrix metalloproteinase 13.In vitro experiments:cartilage cells were cultured and divided into four groups,control group,interleukin-1β group,IL-1βwith AG group and AG group.The first group used the normal cell,the second group of cell culture medium were added with 10 ng/ml IL-1β,the third group of cell culture medium were added with 10 ng/ml IL-1β and 3 mmol/L(369.36 mg/L) AG,the fourth group of cell culture medium was added 3 mmol/L(369.36 mg/L) AG.Protein of the cartilage cells were extracted and the cell culture medium was retained.We detected the vitality of inducible nitric oxide synthase and the content of nitric oxide in four groups of cell culture medium.The concentrations of matrix metalloproteinase-3 and matrix metalloproteinase-13 in four groups of cartilage cells were measured.Result:In vivo experiments,i NOs vitality,NO content,MMP-3 and MMP-13 concentrations in model group were significantly increased relative to the control group.After injection AG,iNOs vitality,NO content,MMP-13 and MMP-3 concentration were significantly reduced relative to the model group.In vitro experiments,i NOs vitality,NO content,MMP-3 and MMP-13 concentrations in IL-1βgroup were significantly increased with respect to the control group.After AG treatment,iNOs vitality,NO content,MMP-13 and MMP-3 concentration were significantly reduced relative to the IL-1β group.The AG group did not have significantly change relative to the control group.Conclusion: Aminoguanidine could inhibit the activity of inducible nitric oxide synthase, and reduce the content of NO in the cartilage.Aminoguanidine indirectly reduced the concentration of MMP-3 and MMP-13,the pathological changes of osteoarthritis cartilage tissue were reduced.