Frontal-parietal brain homogenates in 3-month old (a–c) and 16-month-old (d–f) TRE3, TRE4 and wildtype controls were analyzed by Western blotting for the levels of laminin (a, d), collagen IV (b, e) and agrin (c, f). Levels of laminin and collagen IV were significantly higher in the brains of 3-month old, but not 16-month old TRE3 and TRE4 mice versus wildtype mice. Agrin levels were unchanged between wildtype, TRE3 and TRE4 mice at either age. Optic density ratios of protein to GAPDH levels from 3 blots per antibody were analyzed by repeated measures two-way ANOVA with Bonferroni post-hoc test. Histograms represent mean optic density ratio values ± S.E.M., *p<0.05, **p<0.01, ***p<0.001.