Ischemic damage visualized in flat mounts of rat retina after photochemically induced thrombosis

The method of photochemically induced thrombosis was used to produce severe ischemia in the rat retina. Flat mounts of the retina were prepared at 3 h, and 1, 2, 3, 4, 6, 7, and 22 days after lesioning and Nissl-stained, which facilitated the study of the topography of the ischemic lesions. The regional variability of ischemic damage and the cytological features of ischemic cell death in the ganglion cell layer were evaluated. Neuropathological analysis showed ischemic cell damage of ganglion cells at 3 h, an infarction-type lesion at 1 to 7 days, and scar formation at 3 weeks. As an additional parameter of ischemic ganglion cell death, the degeneration of retinal axons was visualized in the contralateral dorsal lateral geniculate nucleus by Fink-Heimer silver impregnation and by immunohistochemical staining for glial fibrillary acidic protein (GFAP) in reactive astrocytes.