Protective effect of taurine against cyclophosphamide-induced urinary bladder toxicity in rats.

1. In the present study, the effect of taurine, on cyclophosphamide (CP)-induced urinary bladder toxicity was investigated. 2. Administration of a single dose of CP (150 mg/kg, i.p.) induced cystitis, as manifested by marked congestion, oedema and extravasation in rat urinary bladder, as well as a marked desquamative damage to the urothium, severe inflammation in the lamina propria, focal erosions and polymorphonuclear leucocytes associated with occasional lymphocyte infiltration as determined by macroscopic and histopathological examination. 3. A significant decrease in the endogenous anti-oxidant compound glutathione and elevation of lipid peroxidation also resulted in rat urinary bladder tissue. 4. Cyclophosphamide-induced cystitis markedly affected the contractile function of the urinary bladder, as revealed by a significant inhibition of tissue responsiveness to acetylcholine (ACh) at different molar concentrations in vitro. 5. Conversely, pretreatment with taurine (1% in drinking water to reach a dose of 1 g/kg per day) for 7 days before and 1 day after CP injection produced a significant decrease in urinary bladder weight (oedema) and a marked decrease in vascular congestion and haemorrhage, as well as a profound improvement in histological structure. Moreover, taurine pretreatment resulted in a significant decrease in lipid peroxide in urinary bladder tissue and glutathione content was greatly restored. 6. Urinary bladder rings isolated from rats treated concurrently with taurine and CP showed a significant increase in their responsiveness to ACh compared with the CP group. 7. These results suggest that taurine offers a protective effect against CP-induced urinary bladder toxicity and may, therefore, decrease the limitation on its clinical application. These results merit extension and further investigation of the impact of taurine on CP antitumour activity.