AIM: To evaluate the expressions and significances of endoplasmic reticulum stress related protein(BIP), hypoxia-inducible factor-1α(HIF-1α)and vascular endothelial growth factor(VEGF)in the retina of diabetic rats.

METHODS: Seventy-two male Sprague-Dawley(SD)rats were chosen and divided randomly into 6 groups: normal control 2mo(C2m, n=12), diabetes mellitus 2mo(D2m, n=12), normal control 4mo(C4m, n=12), diabetes mellitus 4mo(D4m, n=12), normal control 6mo(C6m, n=12)and diabetes mellitus 6mo(D6m, n=12). The diabetes mellitus mouse were induced by intraperitoneal injection of 0.1mol/L streptozotocin(STZ, 65mg/kg). The expression of BIP, HIF-1α and VEGF in the retina were detected by enzyme-linked immuno sorbent assay. The location of BIP, HIF-1α and VEGF in epiretinal membranes were investigated by immunohistochemistry staining.

RESULTS: BIP were significantly increase than control groups in all DM groups with the course of diabetes(P<0.01). HIF-1α were detected higher than control groups in all DM groups(P< 0.05), but there was no statistical significance among treatment groups. VEGF in D4m and D6m groups were higher than control groups(P<0.05), and there was statistical significance between D4m and D6m groups. BIP can be detected in control groups a little, mainly in the inner limiting membrane and ganglion cell layers. HIF-1α cannot be detected in control groups, meanwhile it can be detected in all layers in DM. VEGF can be detected in control groups a little, it mainly be detected in inner nuclear layer, outer nuclear layer, around retinal vessel and ganglion cell layers in DM groups.

CONCLUSION:The expressions of BIP, HIF-1α and VEGF increase in the retina of diabetic rats than control groups with progressive of diabetes mellitus, both endoplasmic reticulum stress and HIF-1α signal path play important role in the progress of diabetic retinopathy.