Anti-cicatricial effect of tetrandrine drug delivery system in glaucoma filtration surgery in rabbit / 中华实验眼科杂志

ABSTRACT

Background Scarring of the filtering bleb is a main cause of filtering surgical failure in glaucoma.It has been reposed that tetrandrine could suppress the proliferation of cultured human fibroblast of Tenons capsule in vitro and thus has the potential effect to prevent scarring after the filtering surgery. Objective Present study was to investigate the anti-cicatricial effect of tetrandrine drug delivery system(Tet DDS)during filtration surgery. Methods Filtration surgery was performed in bilateral eyes of 18 New Zealand white rabbits.The Tet DDS with 0.3 mg Tet,0.2 mg Tet or free-Tet were implanted subcunjunctially during the surgery.The filtering blebs were scored in 1 day,4,7,10,14 days after referring to the corneal thickness and bleb range under the slit-lamp biomicroscopy.The morphology of filtering bleb was assessed by in vivo confocal microscopy in 7 and 14 days after operation.The filtering bleb specimen was prepared in 7 and 14 days for the histopathological examination. Results The filtering bleb scores in Tet DDS implantation groups were significantly higher than those in free-Tet DDS group from 4 days through 14 days after trabeculectomy(P＜0.01),and the scores showed a considerably increase in 0.3 mg Tet DDS group compared with 0.2 mg Tet DDS group from 7 days through 14 days after trabeculectomy(P＜0.05).The filtering blebs of Tet DDS implantation groups were found with distinct subepithelial cystic spaces under the light microscopy and in vivo confocal microscopy on the 7th day and 14th day after surgery.Compared with free-Tet DDS group,the numbers of subepithelial mierocysts were much more(P＜0.01)and the area of microcysts was larger(P＜0.01)in Tet DDS group.The filtering tissue presented with more subepithelial microcysts and larger microcysts range in 0.3 mg Tet DDS group than 0.2 mg Tet DDS group in 7 and 14 days after operation(P＜0.05).The inflammatory cell infiltration wag milder in 0.3 mg Tet DDS group in comparison with 0.2 mg Tet DDS group and free-Ted DDS group.Conclusion Tet DDS has strong inhibitory effects on inflammatory cells activity and fibroblagt activity the early stage after filtering surgery and therefore improve the surgery success rate.