Low susceptibility of analbuminemic rats to induction of bladder cancer by N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide.

The susceptibility of analbuminemic rats (Nagase analbuminemic rats; NAR) to induction of bladder cancer by oral N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) was studied. Male NAR and Sprague-Dawley rats (SD) were fed normal diet or normal diet supplemented with 0.2% FANFT for 10 weeks and killed in week 52. Bladder cancer was found in 5 of 24 SD (21%) but not in 18 NAR (0%). Proliferative lesions of the bladder epithelium, which are considered to be precancerous or more advanced than precancerous changes, were found in 16 of 24 SD (67%), but in only 4 of 18 NAR (22%). NAR showed lower susceptibility than control SD to induction of bladder cancer by FANFT.