Fig. 2.

Quantification of the volume of the ipsilateral projection to the dLGN in wild-type and MAOA-KO mice. To estimate the volume of the dLGN receiving projections from the ipsilateral eye, the area of the dLGN covered by HRP reaction product in each section after intraocular injection of HRP, was measured using an image analysis program. The volume occupied by the terminals from the injected eye was calculated by multiplying the area measured by the thickness of each section (40 μm) from serial coronal sections through the dLGN. Totals are shown in cubic millimeters for wild-type C3H/HeJ mice at P3 (n = 4; mean ± SEM = 0.0102 ± 0.0013), P8 (n = 3; mean ± SEM = 0.0085 ± 0.0018), and P30 (n = 7; mean ± SEM = 0.0151 ± 0.0007) (white bars); for MAOA-KO mice at P3 (n = 4; mean ± SEM = 0.0094 ± 0.0013), P8 (n = 4; mean ± SEM = 0.0192 ± 0.0024), and P30 (n = 4; mean ± SEM = 0.0235 ± 0.0009) (black bars); and for adult MAOA-KO mice treated with PCPA during the first 15 postnatal days (n = 2; mean ± SEM = 0.01527 ± 0.0008) (striped bar). Values for MAOA-KO mice that differ significantly from wild-type are indicated by an asterisk above the bar (p ≤ 0.01, using Student’s unpairedt test). At P3, the ipsilateral projections of wild-type and MAOA-KO mice occupy the same volume of the dLGN, whereas at P8 and P30, the ipsilateral projection in MAOA-KO mice is significantly larger than in wild-type animals. The ipsilateral projections of MAOA-KO mice treated with PCPA occupy the same volume as those of wild-type mice. Error bars indicate the SEM for each value.