Fig. 10.

Shh overexpression leads to aganglionosis and modifies CS-56 immunostaining in the mouse hindgut. At E12.5, p75⁺ ENCCs have migrated into the mid-hindgut (A, section 2), and the distal hindgut is still aganglionic (A, section 3). ENCCs do not co-immunostain with Ptc1 (B). After 48 h in culture (n=15), ENCCs complete their migration into the distal hindgut and CS-56 immunostaining is observed (C). Addition of cyclopamine to the cultured gut does not inhibit ENCC migration, but reduces CS-56 immunostaining in the outer mesenchyme (D). Addition of Shh inhibits ENCC colonization, leading to distal aganglionosis, and increases CS-56 immunostaining throughout the mesenchyme (E).