Hepatic necrosis in aged mice by oral administration of microcystin-LR.
Aged mice (32 weeks) were orally administered microcystin-LR at 500 micrograms/kg, and injuries of the liver were estimated by microscopy 2 hr after treatment. Sixty-two per cent of aged mice proved to be sensitive to microcystin-LR, whereas such changes in the liver were not found in young mice (5 weeks). Uptake of the toxin into the liver was confirmed by high-performance liquid chromatography and frit-fast atom bombardment liquid chromatograph/mass spectrometry after clean-up with an immunoaffinity column. To verify the difference in sensitivity to microcystin-LR between aged and young mice, non-treated mice were examined, and among them aged mice were confirmed to have a rough surface of the stomach and small intestinal mucosa. These results suggested that the hepatotoxicity by oral administration of microcystin-LR is deeply related to aging, and particularly to conditions in the small intestine such as the permeability of capillaries in the villi.
Ito
E
E
Research Center for Pathogenic Fungi and Microbial Toxicoses, Chiba University, Japan.
Kondo
F
F
Harada
K
K
D000284:Administration, Oral; D000375:Aging; D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D002851:Chromatography, High Pressure Liquid; D004791:Enzyme Inhibitors / Q000633:toxicity*; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D008387:Marine Toxins / Q000633:toxicity*; D051379:Mice; D052998:Microcystins; D009336:Necrosis; D010456:Peptides, Cyclic / Q000633:toxicity*
D004791:Enzyme Inhibitors; D008387:Marine Toxins; D052998:Microcystins; D010456:Peptides, Cyclic; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; C057862:cyanoginosin LR