Fig. 6. Exogenous retinoids improve striatal neuron differentiation in the Gsh2 mutant. At E18.5, DARPP-32 expression (detected by IHC) is increased at all levels of the striatum in the RA-treated Gsh2 mutants (B,D) compared with vehicle (oil)-treated Gsh2 mutants (A,C). RA treatment of the Gsh2 mutants does not alter striatal size, as marked by Foxp1 staining (F,H). Indeed, the size of the RA-treated striatum appears to be very similar to that of the control oil treatments (E,G). GP, globus pallidus.