MPTP-induced gliosis. (A–C) Immunohistochemical staining for GFAP in the striatum in DAT-Cre (A), Retlx (B), and DAT-Retlx/lx (C) mice. (D–F) There is a robust increase in GFAP-positive reactive astrocytes at 14 days after MPTP treatment, with no difference among genotypes. (G–I) At 90 days, the number of GFAP-positive astrocytes is back to baseline levels. (Scale bar, 100 μm.)