Glaucoma is an optic neuropathy that causes loss of retinal ganglion cells (RGC) and lead to blindness. This disease is a leading cause of blindness and visual impairment worldwide. For pre-clinical studies and finding novel therapies recruiting functional and easy-to-utilize animal models is necessary. One of the reliable models is N-methyl D-aspartic acid (NMDA) induced mice. Generation of this model characterizes by rapid RGCs loss followed by gradual reduction in ganglion cell complex (GCC: retinal nerve fiber layer, ganglion cell layer, and inner plexiform layer) thickness. Here we report generation of a mouse model by utilizing NMDA excitotoxic amino acid.

Retinal cell damage was induced in vivo in mice by intravitreal injection of NMDA (40 nanomoles). After 3 days, treated eyes enucleated and histological analysis was performed in NMDA and PBS injected eyes and in normal mice. Retinal ganglion cells were counted in a distance of 400 µm using light microscopic images after H and E staining. Thickness of the retina and GCC around the 400 µm of the optic nerve disc were measured. Moreover, we compared outer and inner nuclear layer (ONL and INL) thickness in samples.

The thickness maps and the quantitative thickness values of retina and GCC showed thickness changes in the NMDA-treated mice when compared with normal and vehicle-treated mice. ONL thickness was not affected, but INL thickness showed small changes. The number of retinal ganglion cells was significantly decreased in treated mice. Normal and vehicle-treated mice were similar in all parameters.

Due to difficulties in human glaucoma studies, development of animal models for the pathophysiological studies is critical. NMDA-induced RGC damage is a reliable method to generate glaucoma model. Histological imaging of the retina provides a sensitive and precise method for evaluation of RGC damage in experimental models of glaucoma. We could achieve to the technics in NMDA injection and subsequent histological analysis in the generation of NMDA-glaucoma mouse model.