Ganglion cell loss after optic nerve crush mediated through AMPA-kainate and NMDA receptors.

PURPOSE Glutamate antagonists can block ganglion cell death due to optic nerve crush. Although most investigators have focused on blockade of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptor, we have chosen to evaluate the efficacy of blockade of the AMPA-kainate (KA) receptor in this experimental paradigm. METHODS The optic nerves of rats were crushed, and ganglion cell survival was assessed. Groups of animals were treated with an NMDA antagonist, an AMPA-KA antagonist, or both. RESULTS The AMPA-KA antagonist DNQX was more effective, although not additive in preserving retinal ganglion cells after optic nerve crush than the NMDA antagonist MK801. CONCLUSIONS Activation of the AMPA-KA subtype of glutamate receptor may play a role in glutamate-mediated cell death after optic nerve crush.