Abstract
Purpose:
Early stages of diabetic retinopathy are characterized by inflammatory changes. The role of several endogenous anti-inflammatory molecules in this disease is unknown. We aimed at evaluating the expression of A1AT in the retina of diabetic and non-diabetic rats.
Methods:
Five male Wistar rats of 250 g were treated with an IP injection of 45mg/kg of streptozotocin (STZ). Animals with glycemia levels above 200 mg/dl were included in the study. Five non-diabetic rats were included as a control group. Animals were sacrificed after 16 weeks of diabetes. Cross sections of retinas were analyzed by immunohistochemistry using a primary antibody against A1AT. Protein expression was also analysed by western blot.
Results:
Retinas of diabetic and control rats showed immunoreactivity of A1AT in the fiber layer, outer plexiform layer and in the external segment of photoreceptors. Higher staining was seen in diabetics. Small vessels were only stained among diabetic animals. No significant differences of protein expression of A1AT were observed between groups by westernblot.
Conclusions:
An increased immunohistochemical staining of A1AT in diabetic rats and a similar protein expression between control and diabetic retinas might suggest a relative insufficient quantity of A1AT among diabetics after 16 weeks of disease. Studies in animals with longer duration of diabetes are being conducted to further evaluate the role of A1AT in diabetic retinopathy.
Keywords: 499 diabetic retinopathy •
557 inflammation •
688 retina