Protective Effects of Melatonin on Retinal Inflammation and Oxidative Stress in Experimental Diabetic Retinopathy

Figure 4

Immunostaining of MT1 and MT2 in nondiabetic and diabetic retinas (a). Immunostaining of glutamine synthase, Brn-3 and NF-κB p65 in nondiabetic retinas (b–d). Nuclei were counterstained with DAPI. In the retinas of nondiabetic rats, specific MT1/MT2 immunolabeling (green) was observed in the ganglion cell layer and in the inner plexiform layer. A further increase in staining intensity of MT1/MT2 occurred at 8 weeks of diabetes. MT1 expression was identified in cells with positive staining of either Brn-3 (b) or glutamine synthetase (c), which are markers of ganglion cells and Muller glial cells, respectively. Immunostaining of the p65 subunit of NF-κB showed colocalization with MT1 expression in the ganglion cell layer (d). Scale bar, 50 μm.

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