Figure 7. Marginal Zone abnormalities in MAM brains.

A–D: Changes in the superficial layer of the MAM brain were first evident at E18 by reelin expression. In the normal rat brain (A), the MZ was a thin layer containing with reelin-positivecells at the surface (C). The MZ in the MAM brain (B) was thicker and had more reelin-positive cells. Higher magnification showed that the MZ was considerably thicker in MAM-exposed animals compared to controls (D). E–H: By E19, reelin-positive cells were still confined to the MZ of control brains (E and G), but in the MAM neocortex the MZ was thickened (F) and many reelin-positive cells were in deeper cortical layers (G). I: Quantification of the number of reelin-positive cells along the surface of the MZ compared the E19 control brain (black bar; 32.6 cells; SEM±2.1) to the E19 MAM-treated brain (white bar; 61.1; SEM ± 5.8; p= 1.3E-05).J: Quantification of the percentage of deep reelin-positive cells that escaped from the MZ (ie were located > 2 cell diameters away from the MZ) in the E19 control and MAM brains. The percent of deep reelin-positive cells was 0.02% in control brains and 42.4% in MAM-treated brains (p=5E-08). ; Scale bars: low magnification = 200mm; high magnification = 100mm