Dynamic expression of heat shock protein 47 in filtering bleb following the glaucomatous filtering surgery in rat / 中华实验眼科杂志

ABSTRACT

Background Anti-scarring is a focus following glaucoma filtering surgery.It has been verified that expression of heat shock protein 47 (HSP47) is always correlated with that of various types of collagens and closely related with the collagen-related diseases including fibrosis in various organs.However,the relationship between the expression of HSP47 and fibrosis of filtering bleb is unclear.Ohjective Present study was to investigate the dynamic expression of HSP47 in subconjunctival filtering bleb after anti-glaucomatous filtering surgery.Methods Filtering surgery was performed on the right eyes of 10 SPF male Spargue-Dawley(SD) rats.Then the operative eyes were randomized into the postoperative 7-day group and 14-day group according to the randomized number table,and the left eyes of the rats served as the normal control group.The shape of filtering blebs and the ocular anterior segment response were examined under microscope daily.The animals were sacrificed by excessive anesthesia on day 7 and 14 after operation,respectively,and the specimens were prepared of the eyes.Regular histopathological examination was performed to observe the collagen fibrosis change,and immunohistochemistry was carried out to assay the dynamic expression of HSP47 depended on the fibrosis.Percentage of positive cells for HSP47 were calculated.The use and care of the experimental animals complied with the Regulation for the Administration of Affair Concerning the Experimental Animals by State Science and Technology Committee.Results Diffuse subconjunctival blebs were seen postoperatively in t0 eyes after surgery with mild inflammatory response in ocular anterior segment.Hematoxylin-eosin staining showed that compared with the specimens of the normal control group,fibroblasts obviously proliferated and collagenous fibers increased in the specimens of operative group.The HSP47 protein was less expressed in cytoplasm of many fibroblasts and less vascular endothelial cells in the normal rat specimens.The expressing intensity of HSP47 protein was enhanced.However,the expression intensity was weaker in the postoperative 14-day group in comparison with the 7-day group.The percentage of positive cells for HSP47 in the filtering blebs 7 days after operation was (56.40±1.12)％,that in the normal control group was (13.70±0.74)％,with a significant difference between them (P=0.000).In the postoperative 14-day group,the percentage of positive cells for HSP47 reduced from (56.40± 1.12) ％ to (23.90±0.76) ％ (P =0.000),but it was still higher than that of the normal control group (P =0.000).Conclusions Expression intensity of HSP47 alters as the activity of fibroblasts in filtering bleb,suggesting that HSP47 plays a role in collagen-fibrosis following filtering surgery in SD rats.