The morphological structure and distribution of asymmetrical unit membrane(AUM)of mouse and bovineurothelium has been observed by means of several electron microscopic techniques,The results indicate thatAUM structure exists not only on the luminal surface and fusiform vesicles in superficial cells,but also on thefusiform vesicles in intermediate cells of mouse。Ruthenium Red staining reveals that there is glycocalyx only onthe AUM area of luminal surface of bladder,Cell extract and DGD-embedding free techni...