Elevated RA synthesis and signaling in the ischemic hemisphere. Compared to the uninjured hemisphere (A), the number of cells expressing RA synthesizing enzymes Raldh1 (red) and Raldh2 (green) increases dramatically 7 days following 60 min MCAO (B). Carets in A and A'
insets mark Raldh1+/Raldh2+ PSCs around vessels in non-ischemic cortex. Arrows in C depict Raldh1+/Raldh2+ PSCs in the lesion. Carets in D indicate CD68+/IB4+ macrophages (green/magenta) express Raldh1 (red) in the lesion core. Graphs depicting quantification of cells expressing Raldh1 (E) and Raldh2 (F) in injured and un-injured hemispheres. Fast LC-MRM3 quantification of RA (G) from left and right hemispheres of uninjured and 60 min MCAO (right hemisphere) animals at 7 days post-injury. A minimum of 3 separate animals were analyzed (n ≥ 3) and error bars represent SEM. Asterisks indicate statistically significant difference (p < 0.05) from uninjured/non-ischemic hemisphere to ischemic hemisphere. DAPI marks nuclei in blue. Scale bars 20 µm (C), 50 µm (A′–A‴), and 100 μm (A, B, D)