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.