A total of 80 rats were randomly divided into control group， model group， positive drug group and treatment group；there were 20 rats in each group.The rheumatoid arthritis model was established with type Ⅱ collagen（Col Ⅱ） induction.The rats in positive drug group were treated with diclofenac sodium sustained-release tablets，and the rats in treatment group were treated with triptolide.After treatment，the body weights， paw thickness and arthritis index scores of the rats in various groups were measured；HE staining was used to determine the pathomorphology of joint synovial tissue of the rats in various groups；immunohistochemical staining was used to determine the microvessel density（MVD） of vascular endothelial growth factor （VEGF） expression level in synovial tissue of the rats in various groups； ELISA method was used to determine the serum levels of VEGF of the rats in various groups；Western blotting method was used to determine the expression levels of PTEN， PI3K， AKT and phosphorylated-AKT （p-AKT） proteins in synovial tissue of the rats in various groups.

Compared with control group， the body weight of rats in model group was decreased （P<0.05）， the paw thickness was increased （P<0.05）， the MVD and expression level of VEGF in synovial tissue were increased （P<0.05）， the expression level of PTEN protein in synovial tissue was decreased （P<0.05）， and the expression levels of PI3K， AKT and p-AKT proteins were increased （P<0.05）.Compared with model group， the body weights of the rats in positive drug group and treatment group were increased （P<0.05），the paw thickness was decreased （P<0.05），the MVD and the expression levels of VEGF in synovial tissue were decreased （P<0.05）， the expression levels of PTEN protein were decreased （P<0.05）， and the expression levels of PI3K， AKT and p-AKT proteins were decreased （P<0.05）.Compared with positive drug group， the MVD and expression levels of VEGF in synovial tissue of the rats in treatment group were decreased （P<0.05）， the expression level of PTEN protein in synovial tissue was increased （P<0.05）， and the expression levels of PI3K， AKT and p-AKT proteins were decreased （P<0.05）.The paw thickness and arthritis index of rheumatoid arthritis rats were positively correlated with VEGF（r=0.564， r =0.492） and p-AKT（r=0.561， r=0.468） （P<0.05），and negatively correlated with PTEN （r=－0.437， r=－0.521）（P<0.05）；MVD was positively correlated with VEGF（r =0.587）， PI3K（r =0.567）， and p-AKT（r=0.601） （P<0.05）， and negatively correlated with PTEN （r=－0.502）（P<0.05）.

Triptolide can inhibit the angiogenesis and PTEN / PI3K / AKT pathway activation in the rheumatoid arthritis rats， thereby exerting its therapeutic effect on rheumatoid arthritis.