Studying the development of the whole mouse ureter in vitro
Whole metanephric organ culture has long been used as an experimental tool for the examination of the direct effects of factors on the growth and differentiation of the kidney. Until recently, no such assay was available for the ureter. However, the development of a mouse ureter culture system was described by David S et al (2005), who cultured partially developed ureters from embryonic day (E) 13.5-15.5 mice. We have modified this method to culture mouse ureters from E12.5. At this earlier timepoint, the ureter consists of a simple, cuboidal epithelial tube surrounded by ureteric mesenchyme and does not express specific markers for urothelium or smooth muscle. Whole ureters with metanephroi attached were cultured in 50:50 DMEM/Hams F12 media supplemented with 1% fetal calf serum, 5μg/mL transferrin, 12.9μL/mL L-glutamine, penicillin (100μg/mL), and streptomycin (100U/mL). The media was changed every 48 hours. A multi-layered urothelium lining a patent lumen was present after 2 days of culture and smooth muscle (assessed by immunohistochemistry for alpha-smooth muscle actin) was present by day 4. Peristaltic contractions of the ureter, commencing at the renal pelvis, were evident from day 7. This assay enables us to directly test the effects of factors on the development of smooth muscle, urothelium and peristalsis in the ureter, before the initiation of their development in vivo.
David SG, et al. c-kit and ureteral peristalsis. J Urol. 2005 173(1):292-5.