TUNEL labeling of ureters.

<p>Transverse sections through ureters with all nuclei stained blue with DAPI; apoptotic nulei are green. The asterisk in each image indicates the ureteric lumen. <b>A</b>. Wild type E16 ureter shows no apoptosis in the double-layered epithelium or in adjacent differentiating smooth muscle. There is a single apoptotic nucleus (arrow) in the nearby peritoneal mesothelium. <b>B</b>. Homozygous <i>p63</i> mutant ureter with two apoptotic nuclei; one (indicated by the arrow on the left) is in the stromal layer immediately outside the epithelial monolayer, while the other (indicated by the arrow on the right) is within loose cells just outside the muscle layer. Bars are 50 μm.