Enhancement of hepatocarcinogenesis initiated with diethylnitrosamine or N-nitrosobis(2-hydroxypropyl)amine by a choline-deficient, L-amino acid-defined diet administered prior to the carcinogen exposure in rats

摘要: Summary Effects of pre-administration a choline-deficient, L -amino acid-defined (CDAA) diet on hepatocarcinogenesis initiated with diethylnitrosamine (DEN) or N -nitrosobis(2-hydroxypropyl)amine (BHP) in rats were investigated. A pre-administrating period was set as 1 week, because CDAA induces liver injuries by this time-point. In time-course study, male Fischer 344 rats, 6 weeks old, received 1-week choline-supplemented, (CSAA) diet, DEN at dose 100 mg/kg body weight single intraperitoneal injection, then CSAA for up to 8 weeks, and sacrificed 4, after DEN. administered only significantly increased the numbers glutathione S -transferase placental form (GSTP)-positive lesions their sizes both before similarly GSTP-positive lesions, but greater degree than obtained response vechicle DEN, 0.001, 0.01, 0.1, 1, 10, 20, 50, 200 weight, week commencement vehicle The significant increases 50–200 under administration, whereas those detected 10–200 administration. Sizes became larger case case. Male Wistar preadministration BHP, 600 1200 sacrificed. GST-P-positive demonstrated increment BHP and, degree, BHP. While did not alter lesions. These results indicate that pre- plus post-administration enhances more only, thus providing sensitive model detect weak carcinogenic potency environmental chemicals.