This thesis investigates the effects of intravesical agents, doxorubicin, mitomycin C (MMC), and epirubicin on release of mediators and inflammatory cytokines from the urothelium, and tissue responses and morphological integrity of the bladder. Intravesical therapy which administers cytotoxic agents into the bladder lumen is an important approach for treatment of superficial bladder cancer. Despite evidence of significant local adverse effects such as chemical cystitis (dysuria, increased urinary frequency and urgency) following this treatment, few studies have assessed their effects on non-malignant tissues of the bladder and the changes in urinary function resulting from this therapy. A better understanding of the mechanisms of bladder toxicity by these agents may lead to the identification of novel approaches forreducing the severity of reported adverse effects. Moreover, the effects of ageing on bladder function were also investigated in this thesis.