FIG. 1.

TCDD increases Wnt10a and Wnt16 transcript abundance in the ventral UGS. C57BL/6J mouse embryos were exposed in utero to vehicle or TCDD (5 μg/kg dam, po) at E15.5 and UGSs were harvested at E16.5. UGSs were sectioned along the sagittal plane and are shown with the urethra on the left pointing down and the bladder on the right. Images are representative of at least eight litter-independent UGSs per treatment group. Within each panel, the boxed area in the left image is enlarged on the right. The purple stain marks transcript localization as assessed by ISH. Wnt10a transcription was restricted to the epithelium (A, B) whereas Wnt16 transcription was restricted to the mesenchyme (C, D). Staining for Wnt10a and Wnt16 in the ventral region of UGSs from vehicle control embryos is minimal to absent. However, staining for both Wnt10a and Wnt16 is detectable in the ventral UGS after exposure to TCDD (arrowheads).