Fig. 1.

Neonatal rats were treated with BMAA (150 mg/kg and 460 mg/kg) or vehicle, and their brains were dissected and processed for MALDI IMS at adult age. A, to identify brain regions affected by BMAA, an initial screening of sagittal brain sections from the left hemispheres of animals in the high-treatment group and vehicle-treated animals was performed. Several areas displayed BMAA-induced changes in peak intensities, including the striatum and hippocampus. B, the striatum was selected for further studies in the full-scale experiment, and coronal striatal cryosections were obtained from the right hemispheres of all 21 animals (control, n = 6; BMAA 150 mg/kg, n = 8; 460 mg/kg, n = 7). For statistical analysis, distinct regions of interest (ROIs) were determined. Histology and ion distribution images of several proteins were used to define the striatum, divided into caudate putamen (CPu) and nucleus accumbens (NAc). The anterior commissure was excluded from the NAc ROIs. C, the spectra from each ROI were exported and analyzed. The peak intensity distribution of individual peaks is visualized in user-defined colors, and the maximum peak intensity in each image was set at 100% (m/z 7725 red Gng2; m/z 6718 green PEP-19; m/z 14,144 blue MBP).