Figure 10. Different geographical distribution of RT97-labeled and OHSt-labeled retinal ganglion cells in retinas with ocular hypertension. These examples of representative left retinas in experimental animals 17 days after lasering the left eye show retinal ganglion cells (RGCs) labeled with 10% hydroxystilbamidine methanesulfonate (OHSt) and RT97, illustrating the near confinement of abnormal expression of RT97 to sectors of the retina that lack OHSt backlabeled RGCs; meanwhile, sectors containing OHSt⁺ RGCs present fewer RGCs with abnormal RT97 staining. To identify RGCs capable of retrograde axonal transport, OHSt was applied to both superior colliculi 1 week before sacrifice. Retinal whole-mounts were immunostained with RT97 antibodies to identify RT97⁺ RGCs. OHSt⁺ RGC isodensity maps were generated by assigning a color code to each of the 36 subdivisions of each individual frame according to its density value within a 45-step color scale, ranging from 0 (dark blue) to 5,625 RGCs/mm² or higher (red). RT97⁺ RGCs are represented as dots over the outline of the retinal whole-mount. A, B: A whole-mount of a representative experimental left retina doubly labeled with OHSt (A) and RT97 (B) illustrates the typical topological distribution of 12,821 OHSt⁺ RGCs and 415 RT97⁺ RGCs throughout the retina in these experiments. Note the lack of correspondence between areas containing OHSt-labeled RGCs (A), which are restricted to a large wedge located between the 5 and 10 o’clock positions, and the RT97⁺ RGCs (B), which are distributed mainly in the opposite area of the retina. The dorsal pole of the retina is orientated at 12 o’clock. C, D: Another whole-mounted representative experimental left retina doubly labeled with OHSt (C) and RT97 (D) illustrates the topological distribution of 10,911 OHSt⁺ RGCs and 269 RT97⁺ RGCs throughout the retina in these experiments. Note the lack of correspondence between areas containing OHSt-labeled RGCs (C) which are restricted to a large wedge between 4:30 and 8:30 o’clock, and the RT97⁺ RGCs (D) found mainly in the opposite area of the retina. The dorsal pole of the retina is orientated at 12 o’clock (scale bar=1 mm).