[Effect of carboquone (esquinone) on the development of urinary bladder tumors in rats induced by N-butyl-N-(4-hydroxybutyl) nitrosamine].

The effect of carboquone (CQ) by intraperitoneal administration on the development of urinary bladder tumors in Wistar strain male rats induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) was studied. Urinary bladder tumors were induced in 9 of 11 rats (81.8%) when they were given 0.05% BBN in drinking water for 8 weeks and then given water without BBN for 12 weeks. When CQ 0.25 mg/kg/day was administered intraperitoneally for 7 days after treatment with 0.05% BBN for 8 weeks, incidence of urinary bladder tumors was 19 of 26 rats (73.1%). When CQ 0.25 mg/kg/weekly was given for 12 weeks after treatment with BBN, incidence of urinary bladder tumors was 17 of 27 rats (63.0%). When CQ 0.5mg/kg. B.W./day was given for 7 days after treatment with BBN, tumors developed in the urinary bladder with low incidence as in 8 of 20 rats (40.0%) (P 0.1). When CQ 0.5mg/kg/weekly was given for 12 weeks after treatment of BBN, urinary bladder tumors were induced in 17 of 22 rats (77.3%). Hematotoxity was not observed in any animals treated with CQ. These results showed that CQ inhibited the development of urinary bladder tumors induced by BBN in rats.