RESUMO
Effects of poisonous mushroom extracts on isolated rat hepatocytes were studied. Though no significant decrease in the cell viability was observed during the incubation of hepatocytes with the extracts at a concentration of 5% (v/v) of Amanita abrupta, A. gymnopus, and A. virosa caused marked decreases in the intracellular glutathione content in sharp contrast to the extracts of A. volvata and A. flavipes. Comparative toxicity tests were carried out for the effects of the extract of A. abrupta, dl-propargylglycine, and alpha-amanitin. The extract of A. abrupta at a concentration of 1% (v/v) caused a marked decrease in the glycogen content, a noticeable elevation in the phosphorylase alpha activity, and a slight acceleration of lipid peroxidation in the hepatocytes. Although dl-propargylglycine decreased the intracellular glutathione content progressively with the incubation time, a significant effect of the chemical on lipid peroxidation and the glycogen content was observed only after prolonged incubation at a concentration of 5 mM. On the other hand, alpha-amanitin exerted a little effect on the hepatocytes at 1 microM. These results have indicated that the intoxication by the extract of A. abrupta on the hepatocytes might not due to independently each component, dl-propargylglycine and alpha-amanitin, but combined effect of these components or unidentified substances.
Assuntos
Alcinos , Amanita , Fígado/citologia , Amanita/análise , Amanitinas/toxicidade , Animais , Sobrevivência Celular , Células Cultivadas , Glutationa/metabolismo , Glicina/análogos & derivados , Glicina/toxicidade , Glicogênio/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Pargilina/análogos & derivados , Pargilina/toxicidade , Fosforilase a/metabolismo , Extratos Vegetais/toxicidade , Ratos , Ratos EndogâmicosRESUMO
An aqueous extract of a poisonous mushroom, Amanita abrupta was injected intraperitoneally into male ICR mice and the acute effects on the liver were studied. Contents of serum glucose and liver glycogen decreased to 60% and 10% of the control levels, respectively, 6 h after injection. Activities of serum glutamic oxaloacetic transaminase and serum glutamic pyruvic transaminase increased to 3- and 8-fold, respectively, 12 h after injection, and the elevated activities were maintained up to 24 h. Activities of the hepatic drug metabolizing enzymes were also reduced 15 h after injection. Histological examination demonstrated massive liver cell necrosis and disappearance of glycogen granules in the liver of the treated animals. Two amino acids, L-2-amino-4-pentynoic acid and L-2-amino-4,5-hexadienoic acid were identified in the mushroom extract. The former caused similar biochemical effects to those of the mushroom extract.