Effects Of Intra-articular Injection Of The P38MAPK Inhibitor OPC On Matrix Metalloproteinase In Articular Cartilage Of Rat Model Of Osteoarthritis

Objective the purpose of this study is:to establish a osteoarthritis model in rat knees by transecting anterior cruciate ligament,observe the effect of intra-articular injection of OPC,a natural and selective p38motigen-activated protein kinase inhibitor,on the expression of matrix metalloproteinase MMP-3,MMP-13in the OA rat knees,and explore the realationship between the MMP-3/MMP-13expressions and severity of OA.Methods twenty SD rats underwent unilateral anterior cruciate ligament transection(ACLT) and then randomly be devided into four group,each group within5rats.A group received0.3ml intra-articular injection of OPC at a high concentration of100μmol/l(once a week) immediately after surgery,group B were treated under the same condition using OPC with a low concentration of50μmol/L.group C just had the operation of ACLT and give no injection, group D had no surgery and injection.all rats were sacrificed eight weeks after surgery.Microscopic and immunohistochemical studies were performed on the cartilage, protein expressions of MMP-3and MMP-13were determined by Western blot.Results Cartilage degradation was significantly milder in group A and groupB than in C group as shown by morphological studies(P<0.05) and immunohistochemical studies(P<0.01).The protein expression of MMP-3and MMP-13in cartilage were significantly lower in groups A and B than in group C (P<0.05).Conclusions OPC can significantly inhibitor the expression of MMP-3and MMP-13and thus protect the cartilage.