Nature and fate of the ureteric membrane closing the primitive ureterovesical opening.
83 albino rat embryos were used to investigate and ascertain the presence of the ureteric membrane closing the mouth of the primitive ureterovesical opening. The membrane is found to be derived from the stratified etithelium lining the urogenital sinus and later the developing urinary bladder. It progressively thins out and bulges in the bladder cavity as a result of the increasing functional differentiation and activity of the developing kidney, where the excreted urine dilates the lower end of the ureter till it forms a small cyst-like dilatation before the membrane finally ruptures. The destruction of the ureteric membrane occurs caudal to its center and is immediately followed by dilatation of the bladder cavity and differentiation of mits musculature and lining epitherlium.
D000818:Animals; D008566:Membranes / Q000196:embryology; D051381:Rats; D014513:Ureter / Q000033:anatomy & histology / Q000196:embryology*; D001743:Urinary Bladder / Q000196:embryology*; D014928:Wolffian Ducts / Q000033:anatomy & histology