ISSN:0260-437X    

DOI:10.1002/jat.2550080502

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe effect of silymarin (100 mg/kg i.p.) on the biochemical indicators of liver damage induced by thallium (10 mg/kg p.o.) was studied in rats. The production of malondialdehyde and the content of reduced glutathione in the liver were measured as indicators of lipid peroxidation. Thallium intoxication increased the serum activities of glutamic pyruvic transaminase, gamma‐glutamyl transpeptidase, alkaline phosphatase and the liver concentration of triglycerides. Thallium decreased the activity of alkaline phosphatase and increased that of gamma‐glutamyl transpeptidase in the liver cell membrane. It also abolished the membrane activity of Na+/K+ATPase. Lipid peroxidation was enhanced by thallium as malondialdehyde production was increased and the content of reduced glutathione was decreased in the liver. Silymarin completely prevented all these changes. It is suggested that thallium toxicity is due, at least in part, to the promotion of lipid peroxidation. The membrane stabilizing effect of silymarin observed in this and in other models of liver toxicity is due to some antioxidant property, possibly related to its ability to scavenge free oxygen radic

ISSN:0260-437X    

DOI:10.1002/jat.2550080503

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe effect of vitamin E on the cadmium‐induced changes of glutathione metabolism was investigated in different brain regions. Daily intraperitoneal injection of cadmium (0.4 mg/kg) for 30 days significantly decreased the concentration of reduced glutathione (GSH), and the activities of glutathione reductase (GR) and glucose‐6‐phosphate dehydrogenase (GPDH) in the cerebellum, cerebral hemispheres and brain stem of rats. Cadmium elevated the levels of oxidized glutathione (GSSG) in cerebellum and cerebral hemisphere regions only, while the GSH/GSSG ratio decreased in all three brain regions. The only effect of intramuscular injections of vitamin E (5 mg/kg) given on alternate days for 30 days was a slight increase in GSH and GR in the cerebral hemispheres. The simultaneous administration of vitamin E and cadmium prevented cadmium‐induced changes in GSH and GSSG levels and in the GSH/GSSG ratio, but the cerebellar GSH remained lowered. Furthermore, vitamin E, with the exception of GR in the cerebral hemispheres, did not prevent cadmium‐induced changes in enzyme activities. As the simultaneous injections of vitamin E reduced cadmium‐induced alterations in glutathione concentration without having any appreciable effect on the activity of related enzymes, it is suggested that the preventive effect of vitamin E is mediated through its antioxidative effect, saving GSH from oxidative destruction in the brain of cadmium

ISSN:0260-437X    

DOI:10.1002/jat.2550080504

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractA highly desirable use of delayed contact dermal hypersensitivity data from animal tests is an accurate prediction of the relative potency of positive agents in humans. Because of the manner in which all such animal tests are performed, the wide variety of exposure conditions and concentrations (which are generally more severe than human exposure conditions) have traditionally made prediction of potency (and therefore the extent of hazard) in humans either impossible or extremely crude. A numerical/graphical method has been developed to adjust results from suitable animal studies of all sorts for exposure conditions and allow for ranking of agents for potency and classification of relative hazards. Results from four animal test systems (MEST, EMT, GPMT and Buehler) are compared with results from human studies to show that all four test systems can generate data that are usable for a relative hazard classification process, though they may vary in their performance characteristics as screens.

ISSN:0260-437X    

DOI:10.1002/jat.2550080505

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractRats were subjected to a chronic ethanol exposure in their drinking water for 8 months and then a short subacute toluene exposure to 12 000 mg/m3for 5 h/day for nine days. Combined exposure increased the reticulocyte count and the concentration of haemoglobin, and changed the biochemical/biophysical properties of red blood cells. Macrocytosis and a decrease in erythrocyte membrane lipid fluidity in the middle zone of the lipid bilayer were the most useful indices of exposure.

ISSN:0260-437X    

DOI:10.1002/jat.2550080506

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractRabbits were exposed to aerosols of lithium chloride in metal concentrations of 0.6 and 1.9 mg/m3(mass median aerodynamic diameter of 1 μm) for 4–8 weeks, 5 days/week, 6 h/day. The lungs were studied by light and electron microscopy, with particular reference to inflammatory changes, structure of alveolar macrophages and alveolar epithelial cells. Macrophages recovered by lung lavage were studied by light and electron microscopy and their oxidative metabolic activity was measured. The content of phospholipids was analysed in lung tissue. Exposure to lithium produced no significant effects. It thus seems that Li+is less toxic to the lung than the other metals investigated with the same test system, e.g. Ni2+, Cd2+, Co2+, Cr3+and Cr

ISSN:0260-437X    

DOI:10.1002/jat.2550080507

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

ISSN:0260-437X    

DOI:10.1002/jat.2550080508

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

ISSN:0260-437X    

DOI:10.1002/jat.2550080501

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY