AIM:To observe the expression of syndecan-1 on epiretinal membranes obtained from patients with proliferative diabetic retinopathy and retina of diabetic rats.

METHODS:SD rats were given intraperitoneal injection of streptozotocin to induce diabetes. Ink perfusion and stretched retina were used to observe the retinal blood vessels. Immunohistochemistry staining was used to detect syndecan-1 protein in the rat retina and epiretinal membranes of proliferative diabetic retinopathy.

RESULTS:In the diabetic rats of 9-week, peripheral retinal blood vessels shaped tortuously, capillary network was significantly reduced, and parts of the capillary perfusion was bad. In the control group, strong positive staining of syndecan-1 was detected in the nerve fiber layer and ganglion cells, moderate positive staining was observed in the inner plexiform layer and outer segments of photoreceptor, and weak positive staining was detected in the outer plexiform layer. In the retina of diabetic rats, syndecan-1 decreased. Moderate positive staining of syndecan-1 was observed in the nerve fiber layer, ganglion cells and outer segments of photoreceptor, weak positive staining was detected in the inner plexiform layer and outer plexiform layer. Among 13 specimens of epiretinal membranes, weak positive staining of syndecan-1 was detected in 8 cases(61.5%)and negative staining was observed in 5 cases(38.5%).

CONCLUSION:Syndecan-1 is down-regulated in the retina of diabetic rats and epiretinal membranes of proliferative diabetic retinopathy.