Macrogilal retinal cells show a bilateral early activation in a mouse model of unilateral laser‐induced experimental glaucoma

Abstract

PurposeTo describe macroglial morphological features of activation after 24 h of unilateral laser‐induced ocular hypertension (OHT) in OHT‐eyes and their contralateral eyes.MethodsAlbino Swiss mice were divided into two groups, naïve (n = 6) and lasered (n = 6). Retinal whole‐mounts were immunolabeled with antibodies against GFAP and MHC‐II.ResultsWith respect to naïve, OHT eyes and contralateral eyes showed different features of macroglial activation in some retinal areas: i) Müller cells were reactive and expressed GFAP; ii) astrocytes were more robust and had more primary and secondary processes; and iii) MHCII was up‐regulated in astrocytes and in some Müller cells. In contralateral eyes, these signs were observed mainly in the periphery. In addition, in the OHT eyes: i) in some retinal vessels near the optic disc, the astroglial reactivity was so intense that the entire vascular walls were sheathed by astroglial cells; ii) in some areas of the retina, astrocytes and Müller cells formed glial scars. iii) MHC‐II immunoreaction in astrocytes varied depending on the retinal area; in those in which MHC‐II immunostaining was less intense, only astrocyte primary processes could be recognized;ConclusionsAt 24 h after unilateral OHT, macroglia showed features of activation not only in OHT eyes, but also in untreated contralateral eyes. Early up‐regulation of MHC‐II in macroglial cells in both OHT retinas and contralateral retinas, suggest an immune system‐related inflammation early after the induction of ocular hypertension.