IOP Induces Changes In The GFAP-Labelled Retinal Area But Not In Astrocyte Number In Mice Retina Contralateral To Experimental Glaucoma

Abstract

Purpose: : To analyse the effects of laser-induced ocular hypertension (OHT) in the astrocytes of contralateral eyes two weeks after lasering.

Methods: : Adult Swiss mice were divided into two groups: naïve (n=6) and lasered (n=6). Retinal whole-mounts were immunostained with antibodies against GFAP. The GFAP-labelled retinal area (GFAP-RA) and the number of astrocytes were quantified.

Results: : In comparison with naïve: i) astrocytes were more robust in contralateral eyes and had a less intense GFAP immunoreaction (GFAP-IR) with fewer secondary processes in OHT-eyes; ii) GFAP-RA increased in contralateral eyes (p<0.032) and decreased in OHT-eyes (p<0.001); iii) there were no differences in astrocyte number in contralateral or OHT-eyes. However, 57.02% (5523 of 9686) of the astrocytes in OHT-eyes had weaker GFAP-IR and fewer secondary processes than did naïve eyes.

Conclusions: : Two weeks of laser-induced OHT caused changesin the GFAP-labelled retinal area but not in astrocyte number in both contralateral and OHT-eyes. On the basis of the astroglial changes detected in the present work, the use of the contralateral eye as an internal control in experimental model unilateral OHT should be reconsidered.

Keywords: retinal glia • intraocular pressure • astrocyte