Fig. 8. The effect of temporary retinoic acid treatment in
Pitx3-/- embryos is maintained at later developmental
stages. (A) Distribution of TH-immunoreactive (TH-IR) neurons in
E18.5 coronal brain sections at the level of the substantia nigra pars
compacta (SNc) of untreated Pitx3+/+ embryos
(A), untreated Pitx3-/- embryos (B),
retinoic acid (RA)-treated Pitx3+/+ embryos (C)
and RA-treated Pitx3-/- embryos (D). (B)
Quantitative analysis of TH-IR neurons in the SNc of E18.5 RA-treated (black
bars) and untreated (white bars) embryos. The average number of TH-IR neurons
per section are expressed as percentage of the number of
Pitx3+/+ embryos ±s.e.m. (n=3 for
untreated Pitx3-/-, RA treated
Pitx3-/- and RA-treated Pitx3+/+
embryos; n=2 for untreated Pitx3+/+ embryos;
Student's t-test; *P
0.01). (C)
Schematic representation of an E18.5 sagittal section showing the position of
the striatal regions (I and II) demonstrated in D. (D)
TH-immunoreactivity at two levels of the striatum of E18.5 embryos. The arrows
mark the dorsal striatal areas in which an increase of TH-immunoreactivity is
observed.