摘要:

The disposition and metabolism of o‐benzyl‐p‐chlorophenol (BCP) were studied in male Fischer‐344 rats. Three days after oral administration of [14C]BCP at 10, 100, or 1000 mg/kg, more than 90% of each dose was excreted in urine and feces. Comparison of disposition after intravenous, dermal, or oral administration indicated that BCP was not completely absorbed from the gastrointestinal tract or skin. Biliary excretion of BCP was dose‐dependent, with proportionally less BCP‐derived radioactivity being excreted in the bile as the dose was raised. The results also indicated that enterohepatic circulation was involved in BCP disposition. The major in vivo metabolites were glucuronyl conjugates of BCP and hydroxy‐BCP. Clutathione conjugates were also present in urine. In vitro metabolism studies support the observation that microsomal oxidation and glutathione and glucuronyl conjugation play major roles in BCP metabolism. Spleen, kidney, and liver contained the highest tissue concentrations of BCP‐derived radioactivity. The presence of more nonextractable BCP‐derived radioactivity in kidney than in liver is compatible with the hypothesis that covalent binding of BCP to renal tissue may be associated with BCP‐induced nephrotoxicity.

ISSN:0098-4108    

DOI:10.1080/15287398609530884

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Polycyclic aromatic hydrocarbons (PAH) were extracted from coal fly ash collected from the electrostatic precipitator of a thermal power plant. The PAH extract was given intratracheally daily to pregnant rats (2 mg/100 g body weight) on'd 18 and 19 of gestation. In addition on d 19 of gestation rats were also given [3H]benzo[a]pyrene intratracheally. Rats were sacrificed on d 20 of gestation, and the distribution of [3H]benzo[a]pyrene radioactivity and PAH of coal fly ash was studied in maternal lung, liver, and placenta, as well as in the liver and lung of the fetus. The radioactivity of intratracheally given benzo[a]pyrene was found in liver (68%), placenta (4%), fetal lung (1.9%), and fetal liver (1.4%) of maternal lung. Intratracheally administered PAH of coal fly ash were translocated to maternal liver and placenta, as well as to the liver and lung of the fetus. PAH of coal fly ash were also metabolized to several minor and major metabolites by maternal lung, liver, and placenta, as well as by the maternal fetal liver and lung. Some of the PAH metabolites in lung and liver were common; however, the major metabolite of liver, M‐16, was different from the major metabolite M‐16 of lung. The major PAH metabolite of placenta, M‐5, and fetal liver, F‐12, were common PAH metabolites. M‐2 and M‐6 of the placenta and F‐5 and F‐10 of the fetal lung were also common.

ISSN:0098-4108    

DOI:10.1080/15287398609530885

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The effect of intratracheal administration of fly ash has been studied on lung micro‐somal and lung surfactant phosphatidylcholine (PC) metabolism in rats using [methyl‐14C]choline and [methyl‐14C]methionine. Fly‐ash administration significantly increased total phospholipids, PC, phosphatidylethanolamine (PE), and phosphati‐dylglycerol (PC) of lung surfactant. Fly‐ash administration stimulated the formation of lung microsomal PC (as measured by the incorporation of labeled precursors) both by the cytidine 5'‐diphosphate (CDP)‐choline pathway and by the N‐methylation pathway, but this stimulation was fourfold higher in the latter case and only twofold higher in the former as compared to the control. Likewise, the secretion of PC formed by the N‐methylation pathway was sixfold higher as compared to the control whereas secretion of PC formed by the CDP‐choline pathway was only threefold higher as compared to the control. Fly‐ash administration further increased total saturation and decreased unsaturation in PC, PE, and lysophosphatidylcholine (LPC) of lung and in PC, PE, LPC, and PC of lung surfactant as compared to the controls.

ISSN:0098-4108    

DOI:10.1080/15287398609530886

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Macrophages obtained by lavage from the lungs of rats exposed to 0.1 or 0.2 mg/m3(0.05 or 0.10 ppm) ozone (O3for 16 h show increased activity as measured in vitro by cell adherence to nylon fiber. A difference in adherence is noticed between macrophages occurring in first or second lung washings. The latter are less sensitive to ozone stimulation. At ozone doses higher than 0.2 mg/m3, the effect disappears and is even negative for second‐washing macrophages after exposure of rats to 0.8 mglm3(0.4 ppm). The increased activity observed after exposure to the lower levels of O3is explained as a defensive reaction of the organism. Failure to stimulate activity or a decrease of activity, observed at the higher O3concentrations, may point to adverse events.

ISSN:0098-4108    

DOI:10.1080/15287398609530887

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

The direct action of ozone on viability and survival of normal and modified mouse lung fibroblasts has been studied. By cell manipulation of fibroblasts in culture, the content of polyunsaturated fatty acids (PUFA) in the phospholipids was increased from about 6% to about 40%. The cellular content of α‐tocopherol (α‐T) (vitamin E) could be drastically enhanced. Vitamin E supplementation to the cell did not subluence the PUFA manipulation. Normal, PUFA, and PUFA(α‐T) fibroblasts were exposed to ozone by bubbling 10 ppm through the cell suspensions for different periods of time (0–6 h). No significant effects of the ozone exposure could be established when normal fibroblasts were used. The PUFA fibroblasts, however, were very vulnerable to ozone toxicity, both in terms of dye uptake (Trypan blue) and cell death (clonogenic ability). When α‐tocopherol was present in the cell (200 ng/106cells), a clear protection against ozone toxicity was found.

ISSN:0098-4108    

DOI:10.1080/15287398609530888

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

THE PYRETHROID INSECTICIDES. Edited byJ. P. Leahey, Taylor and Francis, Philadelphia, 1985, 440 pp., $81.00.

ISSN:0098-4108    

DOI:10.1080/15287398609530889

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

ISSN:0098-4108    

DOI:10.1080/15287398609530873

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor