Growth factors in bladder epithelium : a study on the expression and functions of growth factors in mouse urothelium

The urogenital tract is one of the major excretory paths for small metabolites and ions. The excreted liquid, urine, is produced by the kidneys, flows through the ureters into the urinary bladder and is finally excreted through the urethra. The mammalian urinary bladder has the important capacity to retain urine for some time. Normally, the bladder is resistant to toxic effects of products in the urine. But after damage to the epithelium of the bladder, bladder epithelial cells may become vulnerable to xenotoxic agents and potential toxic metabolites in the urine. In general, this damage will be repaired by physiological processes. During neoplasia, e.g. in transitional cell carcinoma, aberrations in physiologically regulated processes occur. This thesis focuses on protein factors that may be involved in the physiology of transitional epithelium of the mouse bladder, and their specific functions. The following paragraphs highlight subsequently the structure and function of the bladder (§ 1) the physiology and causes of abnormal growth of the urothelium (§2), proteins that have been shown to be involved in the physiology of normal and tumour cells (§3), what is currently known about these proteins with respect to the bladder (§3.5), and finally the aim of the thesis (§4).