Non-urotoxic induction of hemorrhagic cystitis by braxin C, a bracken toxin, in guinea pigs.

Single subcutaneous injections of 5 and 10 mg/kg of braxin C (BC), ptaquiloside, a toxin isolated from bracken fern, have been shown to induce hemorrhagic cystitis in guinea pigs. In order to determine whether the hemorrhagic cystitis induced by BC is due to the urotoxic effects or not, BC was administered to the guinea pigs in which the flow of urine to the urinary bladder had been intercepted by cannulation of the ureters under anesthesia. In the animals treated ureteral cannulation, edema and hemorrhage were observed in the urinary bladder following BC administration (10 mg/kg s.c.). These findings suggest that BC induced hemorrhagic cystitis is mediated by hematogenous and not urotoxic factors.