Abstract
Purpose: :
to compare the immunohistochemical expression of GFAP and RAGE in the retina of three different models of experimental diabetes.
Methods: :
Type 2 diabetes models were constituted by two groups of four male Wistar neonatal rats that received an intraperitoneal injection of 90 mg/kg and 45 mg/kg streptozotocin (SZT) at day 2 of life, respectively. Rats with lower doses of STZ were fed by a high fat diet (HFD) from week 8 to sacrifice. Type 1 model was made up of adult male rats treated with an intraperitoneal injection of 45 mg/kg STZ. All animals, including control non-diabetic group, were sacrificed at 37 weeks of diabetes. Retinas were processed and analysed by immunohistochemical techniques using GFAP and RAGE antibodies.
Results: :
The immunoreactivity of GFAP found in the fiber layer of diabetic animals was much higher than that seen in controls. In addition, staining of the fiber layer and Muller like-cells was stronger in type 1 diabetics. RAGE expression was seen in the fiber layer and ganglion cell layer of diabetic rats. However, a positive immunoreactivity in the internal nuclear layer was observed in type 1 and type 2 diabetic rats with HFD.
Conclusions: :
Different localization and intensity of the expression of GFAP and RAGE in type 1 and type 2 diabetic rats could be useful to better know the process of oxidative stress and oxidation in the pathophysiology of diabetic retinopathy.
Keywords: diabetic retinopathy • retina • retinal degenerations: cell biology