ABSTRACT
AIM:Receptor tyrosine kinase (RTK) activation is critical for growth factor-mediated cell proliferation. The present study was designed to determine the effect of the tyrphostin AG1295 and AG1296, a selective blocker of PDGF βand αRTK,on proliferative vitreoretinopathy (PVR) development.METHODS:Rabbit conjunctival fibroblasts (RCF) cells were cultured.The effects of AG1295, AG1296,PDGF-AA and PDGF-BB on RCF proliferation are evaluated by MTT assay.Homologous rabbit conjunctival fibroblasts were injected intravitreally to make animal PVR model, followed by injection of 100μmol/L of AG1295 or AG1296 respectively. The presence of tractional retinal detachment (TRD) was assessed to evaluate the effect of AG1295 and AG1296 in vivo .Electroretinography and histologic studies were performed after intravitreal injection of AG1295 into untreated eyes to evaluate toxicity. RESULTS: Both AG1295 and AG1296 (10μmol/L) significantly inhibited rabbit conjunctival fibroblast cell growth stimulated by PDGF-AA or -BB in vitro.Development of TRD was significantly reduced (P<0.05) with 100 μmol/L of AG1295 or AG1296 in vivo, but the effect of AG1295 only present till day 14. Inhibitive effect of AG1296 is longer than that of AG1295.No significant histologic or retinal functional damage was found in both drug-treated groups. CONCLUSION: PDGF αand βreceptor specific inhibitor AG1296 and AG1295 attenuated PVR without significant side effects in rabbits, and AG1296 was better than AG1295. The much longer and stronger therapeutic effect from PDGFαreceptor inhibitor indicated that PDGF α receptor is more important in the development of PVR, and inhibition of this pathway could be a useful treatment alternative to prevent PVR.