The influence of heat shock protein 27 sensibilization to retinal ganglion cells apoptosis of rats

Abstract

Objective To observe the influence of heat shock protein 27 (HSP27) sensibilization to retinal ganglion cells (RGC) apoptosis of rats.Methods Thirty-five female Wistar rats were randomly divided into HSP27 sensibilization group (15 rats),borate buffer solution (BBS) control group (15 rats) and normal group (5 rats).The rats in HSP27 sensibilization group were received hypodermic injection in rear limb with 100 μg HSP27 and complete freund adjuvant,intraperitoneal injection with 1 μg pertussis toxin.The BBS control group received the same volume of BBS at the same site.The normal group received no intervention.The intraocular pressure was measured 3 days before injection and 1,2,4,6,8 weeks after injection.Four,6 and 8 weeks after injection,the retinal frozen sections was made to observe RGC apoptosis by terminal-deoxynucleoitidyl transferase mediated nick end labeling.The anti-HSP27 level in serum and cerebrospinal fluid were detected by enzyme linked immunosorbent assay.Results There was no obvious change of intraocular pressure in rats in 3 groups before injection (P＞0.05).RGC apoptosis was observed in HSP27 sensibilization group 4 weeks after injection,and increased significantly at 6 weeks after injection.There was no RGC apoptosis in BBS control group and normal group.The level of anti-HSP27 in serum and cerebrospinal fluid of HSP27 sensibilization group occurred at 4 and 6 weeks after injection respectively,decreased with prolongation of injection time.Compared with BBS control group and normal group,the RGC apoptosis rate,anti-HSP27 level in serum and cerebrospinal fluid of HSP27 sensibilization group were significantly increased (P＜0.05).There was no significant difference of the RGC apoptosis rate,anti-HSP27 level in serum and cerebrospinal fluid between BBS control group and normal group (P＞0.05).Conclusions HSP27 sensibilization could promote the RGC apoptosis.The variation trend of antiHSP27 level in cerebrospinal fluid is consistent with the RGC apoptosis. Key words: HSP27 heat-shock proteins/drug effects; Apoptosis; Animal experimentation