The Chang In Histopathology Of Synovium And IL-1β And TNF-α Of Synovial Fluid In The Rabbit Knee Osteoarthritis

Objective To investigate the changes in synovium pathologic histology, and the fluctuation of the levels of interleukin-1beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) of synovial fluid(SF) in the rabbit knee joint with osteoarthritis(OA),as well as to discuss the effect of them in the pathological processes of Knee osteoarthritis and reliability to reflect the severity of cartilage degeneration.Material and methodThe synovial membrane and fluids in osteoarthritis was studied using the experiment- al model of osteoarthritis replicated by modified Hulth's modeling method. Both knees were performed in 25 rabbits(50 knees) used as experimental group. The speci- mens in experimental group were collected on week 4,week 6,week 8 after operation. 5 normal rabbits (10 knees) were used as control group. The specimens in control gro- up were collected on week 8.Light microscope was used to investigate the morpholo- gyical change of synovium. The density of cytokines(CK) such as IL-1βand TNF-αin synovial fluid was detected by Enzyme- linked immunosorbent assay (ELISA).Results1. Marked fibrosis and lymphocytic infiltration and vascular proliferation were found in the thickened intima ,2. The levels of IL-1βand TNF-αin SF from OA were significantly higher than those of control group.(P<0.01).3. Inconsistent with the severity of cartilage degeneration ,IL-1βand TNF-αlevels gradually decreased from week 4, between the 4th ,6th and 8th modeling group had not statistical signification(p>0.05).Conclusion1. The high levels of IL-1βand TNF-αmay be induced by the evident synovitis, mediating cartilage degeneration in OA.2. Both IL-1βand TNF-αwere involved in the progression of osteoarthritis,however, respecting the fluctuation in the aggressive-phase , they could not be purposely used as a reliable clinical reference index for OA.