OBJECTIVE: To study the autoimmune injuries on diabetic retinopathy (DR) and the protective effects of immunosuppressive therapy with cyclosporine A (CsA) on the DR of streptozotocin (STZ)-induced diabetic rats. METHODS: STZ-induced diabetic rats were randomly divided into 3 groups: group 1: diabetic group without any treatment; group 2: insulin-treated group; group 3: CsA-treated group which was further divided into 2 subgroups: subgroup A: CsA was given 1 week before hyperglycemia appeared and subgroup B: CsA was given one week after hyperglycemia appeared. Subgroup A and subgroup B were further subdivided into 3 groups respectively, based on the dose of CsA (1, 4 and 8 mg x kg(-1) x d(-1)). As a control group, normal rats were also simultaneously monitored. The pathologic changes in the retina were investigated with HE stain and the deposition of immunoglobulins was detected with immunohistochemistry and immunofluorescent microscopy. RESULTS: After 8 week, the deposition of IgG, IgA and IgM was quite significant in the retina of diabetic rats. The data also suggested that insulin treatment had no effects on the DR. In contrast,with CsA intervention, the deposition of immunoglobulins on the retina of diabetic rats vanished. CONCLUSIONS: Autoimmune injuries were shown, in the present study, to play a critical role in the pathogenesis of diabetic retinopathy. Immunosuppressive treatment with CsA showed protective effects by inhibiting the deposition of immunoglobulins in the retina of diabetic rats.
OBJECTIVE: To study the autoimmune injuries on diabetic retinopathy (DR) and the protective effects of immunosuppressive therapy with cyclosporine A (CsA) on the DR of streptozotocin (STZ)-induced diabeticrats. METHODS:STZ-induced diabeticrats were randomly divided into 3 groups: group 1: diabetic group without any treatment; group 2: insulin-treated group; group 3: CsA-treated group which was further divided into 2 subgroups: subgroup A: CsA was given 1 week before hyperglycemia appeared and subgroup B: CsA was given one week after hyperglycemia appeared. Subgroup A and subgroup B were further subdivided into 3 groups respectively, based on the dose of CsA (1, 4 and 8 mg x kg(-1) x d(-1)). As a control group, normal rats were also simultaneously monitored. The pathologic changes in the retina were investigated with HE stain and the deposition of immunoglobulins was detected with immunohistochemistry and immunofluorescent microscopy. RESULTS: After 8 week, the deposition of IgG, IgA and IgM was quite significant in the retina of diabeticrats. The data also suggested that insulin treatment had no effects on the DR. In contrast,with CsA intervention, the deposition of immunoglobulins on the retina of diabeticrats vanished. CONCLUSIONS:Autoimmune injuries were shown, in the present study, to play a critical role in the pathogenesis of diabetic retinopathy. Immunosuppressive treatment with CsA showed protective effects by inhibiting the deposition of immunoglobulins in the retina of diabeticrats.