Figure 4

Plastic sections of P1 and P3 WT and Lama1^nmf223 eyes. JB-4 sections of P1 WT peripapillary (A) and midperiphery (B) retina show astrocytes (arrowheads) in retina and VHP (arrows) in vitreous. Sections from P1 Lama1^nmf223 retinas stained with hematoxylin and PAS (C, D) showed the VHP in vitreous (arrows) as well as astrocytes in the retina (upward arrowhead) and on the vitreal surface of the ILM (downward arrowhead). Astrocytes were only observed in the retina within the peripapillary region (C). Beyond this point, these glial cells (downward arrowheads) were found on the vitreal aspect of the ILM (C). Astrocytes were not observed in the retina peripheral to traversing the ILM (D). TEM analysis of P1 Lama1^nmf223 retina (E-G) showed the ILM (open arrowheads) and astrocytes on both the vitreal (solid downward arrowheads) and retinal sides of the ILM (solid upward arrowhead). The ILM is incomplete in this area having only a single lamina. Müller cell endfeet (asterisk) can also be seen protruding through the ILM in an area where this structure is otherwise complete (G). JB-4 analysis of P3 whole eyes demonstrated the migration of retinal blood vessels (arrows) from the retina into the vitreous (H). In a neighboring section, the retinal vessels and VHP (paired arrows) can be seen anastomosing in the vitreous (I). Open arrowheads indicate the ILM. Scale bars indicate (A-D, E-F: 20 μm; C, D: 1 μm, G: 2 μm).