Figure 6.

Age-related accumulation of basement membrane proteins in cortical capillaries of TGF-β1 mice. Ultrathin cortical brain sections from TGF-β1 mice (line T64 heterozygous) and nontransgenic littermate controls (Non-tg) at 4, 9, and 18 months of age were analyzed by electron microscopy. The thickness of the basement membrane was measured in seven to nine capillary profiles per brain in a total of three mice per group by computer-assisted morphometry as described in Materials and Methods. Results are means ± SEMs. Basement membranes were significantly thicker in capillaries from TGF-β1 brains than in capillaries from nontransgenic control brains (*P < 0.005; unpaired, two-tailed Student’s t-test).