Figure 4.

Thickening of capillary basement membrane was observed in transgenic retinas. (A) Confocal analysis of retinal capillaries in paraffin sections of retinas immunohistochemically marked with anti-collagen IV (green). Nuclei were counterstained with propidium iodide (red). (B) Transmission electron microscopic analysis of retinal capillaries (upper panels). Thickening of basement membrane (arrows) of transgenic retinas is shown (lower panels, magnification of insets in corresponding upper panels). (C) The basal membrane thickness was measured as indicated in Methods. Results are mean ± SEM of five mice in each group. **P < 0.01. Er, erythrocyte. Scale bars: 5.6 μm (A), 2.7 μm (B, upper panel), and 487 nm (B, lower panel).