Figure 1

Histopathological changes in different studied groups; control group (group I), E. coli group (group II), nitrosamine precursors group (group III), and E. coli and nitrosamine precursors group (IV). (a): Urinary bladder of rat in control group (group I) showing normal histological structure of the lining mucosal epithelium (m), underlining lamina propria (p) and muscularis (ml). (b): Urinary bladder of rat in E. coli group (group II) at 3 months showing focal inflammatory cell infiltration (arrow) with sever dilatation of blood vessels in the lamina propria (c): Urinary bladder of rat in E. coli group (group II) at 6 months showing focal hyperplasia and stratification in the mucosal epithelium (m). (d): Urinary bladder of rat in E. coli group (group II) at 9 months showing dysplasia in the mucosal lining epithelium (m) with inflammatory cells infiltration in lamina propia (arrow). (e): Urinary bladder of rat in nitrosamine precursors group (group III) at 3 months showing dysplasia in the mucosal lining epithelium (d) with degenerative changes (s). (f): Urinary bladder of rat in nitrosamine precursors group (group III) at 6 months showing dysplasia in the mucosal epithelium (s) with congestion of newly formed blood capillaries in underlining lamina propria (arrow). (g): Urinary bladder of rat in nitrosamine precursors group (group III) at 9 months showing dysplasia in the lining mucosal epithelium (s). (h): Urinary bladder of rat in E. coli and nitrosamine precursors group (group IV) at 3 months showing hyperplasia with polyp formation (h) and degeneration (arrow) in mucosal lining epithelium. (i): Urinary bladder of rat in E. coli and nitrosamine precursors group (group IV) at 6 months showing degeneration and dysplasia (h) in mucosal lining epithelium with inflammatory cells infiltration (m) in underlying lamina propria. (j): Urinary bladder of rat in E. coli and nitrosamine precursors group (group IV) at 9 months showing hyperplasia and dysplasia (s) in mucosal lining epithelium.