Neoplastic nodular formation in mouse liver induced by repeated intraperitoneal injections of microcystin-LR.
Neoplastic nodules were observed in mice liver treated with microcystin-LR (MCLR) by the intraperitoneal (i.p.) route over 28 weeks. After 100 i.p. injections of a sublethal dose (20 micrograms/kg) of MCLR, neoplastic nodules were observed without the use of an initiator. Multiple neoplastic nodules up to 5 mm in diameter were observed in the liver of mice in both groups, i.e. those injected 100 times i.p. and those injected 100 times with a 2 month withdrawal. The cysteine conjugate of MCLR was detected mainly in the affected livers. In contrast, when 80 micrograms/kg was orally administered 100 times, characteristic chronic injuries such as fibrous changes and nodule formation were not observed.
Ito
E
E
Research Center for Pathogenic Fungi and Microbial Toxicoses, Chiba University, Japan.
Kondo
F
F
Terao
K
K
Harada
K
K
D000818:Animals; D001427:Bacterial Toxins / Q000633:toxicity*; D007274:Injections, Intraperitoneal; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced*; D008387:Marine Toxins; D051379:Mice; D052998:Microcystins; D010456:Peptides, Cyclic / Q000008:administration & dosage / Q000378:metabolism / Q000633:toxicity*
D001427:Bacterial Toxins; D008387:Marine Toxins; D052998:Microcystins; D010456:Peptides, Cyclic; C057862:cyanoginosin LR