MMP9 and glaucoma: Accordingly, several studies in rodent models of glaucoma, induced by ischemia-reperfusion injury [11, 13–16], N-methyl-D-aspartic acid (NMDA), and kainic acid-mediated excitotoxicity [10, 12], optic nerve transection [17], and ocular hypertension [18], revealed increased MMP-9 activity in the retina, which positively correlated with RGC death.