Chronic ischemia induces regional axonal damage in experimental primate optic neuropathy

Abstract

Objectives: To evaluate the effects of chronic optic nerve ischemia in a nonhuman primate model and to evaluate the regional variability of axonal loss. Methods: Unilateral ischemic optic neuropathy was induced by administration of endothelin-1 to the retrobulbar space via osmotic pumps in 12 primates for 6 to 12 months. The transversely cut sections were stained and divided into 16 regions. Average axonal density in each region was quantified and compared with the untreated contralateral control eyes. Results: Mean axonal density was 208 310/mm2 and 220 661/mm2 in treated and control eyes, respectively (P = .03, 1-tailed paired t test), for the entire group. Two-way analysis of variance sho..