Toxicity of Aristolochiae radix in F344 rats

13-week orally repeated dose toxicity was investigated to ascertain the toxic effects of Aristolochiae radix in F344 rats at dose levels of 0, 1 (0.003 AA, aristolochic acid, mg/kg), 5 (0.014 AA mg/kg), 25 (0.068 AA mg/kg), 125 (0.34 AA mg/kg), and 500mg/kg (AA 1.36 mg/kg). No mortalities were found in any of the dose groups including vehicle control groups of both sexes during the study period. Hematologic and serum biochemical examinations revealed no changes related to the test item in any of the dose groups of both sexes. However, gross findings at necropsy implicated thickening of the stomach wall. In histopathological examinations, prominent findings related to the test item treatment were observed in the stomach and urinary bladder. There were squamous cell papilloma, squamous cell hyperplasia, ulceration and erosion observed in the non-glandular stomach. Squamouse cell hyperplasia was observed at dose levels of more than 125 mg/kg in both sexes and squamous cell papilloma was observed at dose level of 500 mg/kg in both sexes. The incidence and severity of these proliferating lesions including squamous cell hyperplasia and squamous cell papilloma increased with dose dependency. Transitional cell hyperplasia was also observed in the urinary bladder at dose levels of more than 25 mg/kg in both sexes and the incidence and severity of the lesion increased with dose dependency. In conclusion, the toxic changes related to the test item treatment were observed in the stomach and urinary bladder, and the no-observed-adverse-effect level (NOAEL) was estimated to be 5 mg/kg/day for both males and females in F344 rats.

청목향 Aristolochiae radix에 있어 F344 랫드의 독성