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  • 1
    Electronic Resource
    Electronic Resource
    Undernutrition during hyperoxic exposure induces CYP2E1 in rat liver (1997)
    Springer
    Archives of toxicology 71 (1997), S. 684-689 
    Details
    ISSN: 1432-0738
    Keywords: Key words CYP2E1 ; Hyperoxia ; Starvation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Induction of cytochrome P450 2E1 (CYP2E1) has been shown to occur through two distinct mechanisms. The first is seen by treatment of rats with acetone, pyrazole, and 4-methyl-pyrazole, which induces CYP2E1 protein without affecting the mRNA level. The second is observed in starvation, diabetes, and obesity, in which an increase of CYP2E1 protein is associated with an increase of the CYP2E1 mRNA. It has been reported by (Tindberg and Ingelman-Sundberg 1989) that hyperoxic exposure (95% O2) induced a several-fold increase of CYP2E1 protein in both the liver and lung of exposed rats without affecting the level of CYP2E1 mRNA. During the course of our previous study which demonstrated hyperoxia-induced specific pretranslational induction of CYP1A1/2 in the liver and CYP1A1 in the lung, we observed a progressive increase of hepatic CYP2E1 mRNA in animals of the hyperoxia group. Hyperoxia is accompanied by some degree of starvation and our earlier experiments were conducted with rats of significantly greater body weight than those used by Tindberg and Ingelman-Sundberg (260 vs 150 g). Thus we reevaluated the changes of CYP2E1 in the current study with the use of food-restricted control, and by utilizing rats of comparable weight (∼150 g) to that utilized by Tindberg and Ingelman-Sundberg. The results obtained in the present study showed that there was a significant increase in the levels of hepatic CYP2E1 mRNA, protein, and p-nitrophenol hydroxylase activity in the food-restricted control group compared to the untreated controls. Rats from the hyperoxia group also demonstrated a similar increase of these three parameters in their livers but showed no significant difference compared with the results of the food-restricted control group. Rats weighing ∼260 g were also examined with similar food restriction and hyperoxia, and the results were essentially similar to those obtained with the younger rats. The lungs of rats from food-restricted control and hyperoxia groups showed no increase of any of the CYP2E1 parameters. The results obtained in the current study, therefore, indicate that hyperoxia has no effect on CYP2E1 expression in both the liver and lung. Increased CYP2E1 mRNA, protein, and p-nitrophenol hydroxylase activity seen in the liver of rats, but not in the lungs, are consistent with the notion that undernutrition during hyperoxia is the underlying mechanism for this induction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002040050445
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  • 2
    Electronic Resource
    Electronic Resource
    Chronic exposure to ozone and nitric acid vapor results in increased levels of rat pulmonary putrescine (1998)
    Springer
    Archives of toxicology 72 (1998), S. 445-449 
    Details
    ISSN: 1432-0738
    Keywords: Key words Ozone ; Polyamine metabolism ; Rat lung ; Putrescine ; Repair
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In the past decade, there has been growing public concern for the human health effects of exposure to environmental pollutants. Ozone (O3) is one of the most reactive components of photochemical air pollution. Despite extensive investigations by many laboratories on the functional, biochemical, and cellular effects of O3 exposure in humans, animals, and in vitro systems, questions remain concerning the potential adverse effects to human health represented by chronic near-ambient exposure to this environmental pollutant. In the present investigation, the influence of inhalation of O3 and nitric acid (HNO3) vapor on polyamine levels was examined in rat lungs. Male F344/N rats were exposed nose-only to 0.15 ppm O3 and 50 μg/m3 HNO3 vapor alone and in combination for 4 hours/day, 3 days/week for a total of 40 weeks. At this time the animals were sacrificed and their lungs were examined for polyamine contents. Exposure to O3 and O3 plus HNO3 vapor caused a significant increase in the putrescine content of the lung compared to the air-exposed controls (P 〈 0.05). The concentrations of pulmonary spermidine and spermine were not significantly increased by exposure to either O3 or HNO3 vapor alone or in combination compared to the air-exposed controls. The role of polyamines in repair and anti-inflammatory processes has been␣discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002040050525
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  • 3
    Electronic Resource
    Electronic Resource
    Effect of hyperoxia on rat pulmonary and hepatic cytochrome P450 monooxygenases (2000)
    Springer
    Archives of toxicology 73 (2000), S. 540-546 
    Details
    ISSN: 1432-0738
    Keywords: Key words Hyperoxia ; CYP1A1 ; CYP1A2 ; Aryl hydrocarbon receptor ; Oxidized tryptophan
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Exposure of adult male rats to hyperoxia (O2 〉 95%) resulted in a tendency for all of the components of the pulmonary cytochrome P450 (P450) system to increase at 48 h after the exposure. However, the most pronounced effect of hyperoxia was observed on pulmonary ethoxycoumarin O-deethylase and ethoxyresorufin O-deethylase activities which were induced 4- and 25-fold respectively after 48 h. In the liver, P450 and NADH b5 reductase were increased after 48 h, while other components of the monooxygenase system remained unchanged. In the hepatic microsomes, contrary to the lungs, aminopyrine N-demethylase activity was decreased after 24 h of hyperoxic exposure (P 〈 0.05) and returned to the control level by 48 h. Similar changes were observed in benzphetamine N-demethylase activity. Aniline hydroxylase activity was decreased after 8 h of hyperoxic exposure (P 〈 0.01) and remained decreased at 24 h (P 〈 0.01) and 48 h (P 〈 0.05). The level of induction of ethoxycoumarin O-deethylase and ethoxyresorufin O-deethylase activities, however, was almost similar in the liver to that observed in the lungs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002040050006
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  • 4
    Electronic Resource
    Electronic Resource
    Morphology of alveolar lining layerThis work is supported by a grant from The National Institute of Health, U.S. Public Health Service, HD-02459 and by a grant-in-aid of The New York Heart Association. (1970)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 167 (1970), S. 389-400 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The extracellular alveolar lining layer (ALL), composed of both surface film and hypophase, is described under different conditions and fixatives.With primary osmium fixation of small blocks the ALL is not preserved. Lamellar and homogeneous osmiophilic bodies are scattered at random within alveoli. Occasionally the surface film remains within an alveolus but the hypophase is not seen. Poor preservation of the ALL is thought to be due to the limited ability of osmium to cross link proteins and to the mechanical deformation of the alveoli which inevitably accompanies the cutting of fresh lung into small blocks. This leads to the escape of alveolar air and a loss of the air-liquid interface.With primary glutaraldehyde fixation of the whole lung, the ALL is well preserved in many alveoli. The hypophase is mostly homogeneous but occasionally contains osmiophilic bodies and lattices. There are no lamellar and homogeneous osmiophilic bodies within the air space of the alveoli when the ALL is preserved, which suggests that primary osmium fixation of tissue leads to the dislodgement of these osmiophilic bodies from the hypophase.The electron densities of the surface film, the hypophase and the capillary fluid are alike in a given preparation but vary considerably with the concentration of the glutaraldehyde solution and the buffer vehicles used. It is pointed out that in phosphate-buffered preparations the hypophase, the basement membrane and the capillary fluid are highly electron-dense which makes difficult the localization of an electrondense tracers.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1091670403
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  • 5
    Electronic Resource
    Electronic Resource
    Inclusion bodies of type II alveolar cells: Species differences and morphogenesisSupported by Research grant HD-02459 from National Institute of Health, U. S. Public Health Service and U-1880 from Health Research Council of the City of New York. (1969)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 163 (1969), S. 525-541 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In order to evaluate pathological alterations of the inclusion bodies of Type II cells in the mammalian lung, normal morphology of inclusions has been studied in rabbit, sheep, rat, mouse, dog, hamster and guinea pig. In rabbit, and sheep the fetal development of the inclusions has also been investigated.After a standard method of fixation, three different types of inclusions have been found in the species studied. The first type of inclusion is seen in the fetal rabbit, fetal sheep, dog, rat and mouse. In these species the inclusions contain heavily osmiophilic, coarsely lamellar material. In all of these species, the inclusions seem to form from an interaction between tubulo-vesicular bodies, located near the Golgi apparatus, and multivesicular bodies. These are certain variations in the appearance of the inclusions among these species.The second type of inclusion is seen in the hamster and guinea pig, in which lightly osmiophilic material accumulates during the maturation of the inclusions. In these species, a granular dense body seems to occupy an important role in the formation of the inclusion bodies.In the third group, the postnatal rabbit and sheep, the inclusions appear vacuolated.It is postulated that the seemingly inconsistent results of the acid phosphatase activity of inclusions in several species may indeed be a reflection of species differences in the mode of formation of inclusion bodies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1091630405
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  • 6
    Electronic Resource
    Electronic Resource
    The freeze-fracture study of alveolar type II cells and alveolar content in fetal rabbit lung (1978)
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 190 (1978), S. 627-637 
    Details
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Freeze-fracture replication technique was utilized to study the morphology of type II alveolar epithelial cells and alveolar contents in the late gestation of rabbit fetuses. It was shown that the lamellar inclusion bodies of type II cells were enveloped by the usual type of unit membrane with membraneassociated particles of 15 nm diameter. The interior of the inclusion bodies was composed of multiple stacks and/or whorls of membranes which were devoid of membrane-associated particles. Small vesicles within the inclusion were found more frequently with this technique than in chemically fixed thin-sectioned preparations.The intra-alveolar contents were comprised of two components; spherical bodies, which were identical to the internal contents of the lamellar bodies of type II cells, and tubular elements. These tubules most often appeared rectangular on cross-fractured faces. Triangular and hexagonal fracture faces were also noted. The tubules were seen to rest on the surfaces of the spherical components. Our observations suggest that the tubular element of the alveolar contents is formed through the interaction between the discharged lamellar body content and the alveolar fluid, and further suggest that at least the major constituent of type II cell lamellar bodies is lipid not bound to protein.Three new observations were made in this study; the absence of membraneassociated particles on the interior of the lamellae of the inclusions, the crossfractured profiles of tubular elements of the alveolar contents, and the occasional multicompartmental nature of type II cell inclusions.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/ar.1091900302
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  • 7
    Electronic Resource
    Electronic Resource
    The distribution of osmiophilic lamellae within the alveolar and bronchiolar walls of the mammalian lungs as revealed by osmium-ethanol treatmentThis work was supported by grant HD-02459 from National Institute of Health, U. S. Public Health Service, and Grant-in-Aid of New York Heart Association. (1972)
    New York, NY [u.a.] : Wiley-Blackwell
    American Journal of Anatomy 134 (1972), S. 203-219 
    Details
    ISSN: 0002-9106
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Osmiophilia of the cellular elements of the alveoli and bronchioles was investigated using the new technique of second osmication with a solution containing a mixture of osmium tetroxide and ethanol. Previously this method was used to reveal osmiophilic periodic lamellae of synthetic dipalmitoyl lecithin and the surface film of the acellular alveolar lining layer of the mammalian lung in thin sections.In the present experiments, much of the osmiophilic content of inclusions in type II epithelial cells became visible only after second osmication with osmium-ethanol but was not visible with the initial osmium tetroxide fixation. The osmiophilic content of the inclusions showed 42 Å periodicity. These results are in accord with those obtained in the study of dipalmitoyl lecithin and the surface film, suggesting that the inclusions are the precursors of the pulmonary surfactant.Several new observations were made with this technique. These include osmiophilic lamellae within Golgi saccules, within the multivesicular bodies of type II cells, in the vesicles of type I epithelial cells, and in the basement membranes of epithelial cells. These observations are consistent with the idea that the Golgi apparatus and multivesicular bodies are closely related to the production of surfactant and that the surfactant may be disposed of by type I epithelial cells after engulfment by pinocytosis. Thereafter, the surfactant may eventually be cleared through the lymphatics.Clara cell granules behaved differently and were thought to be an unlikely site for the synthesis of the pulmonary surfactant.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aja.1001340206
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  • 8
    Electronic Resource
    Electronic Resource
    Osmiophilia of the saturated phospholipid, dipalmitoyl lecithin, and its relationship to the alveolar lining layer of the mammalian lungThis work was supported by grant HD-02459 from National Institute of Health, U. S. Public Health Service and Grant-in-Aid of New York Heart Association. (1971)
    New York, NY [u.a.] : Wiley-Blackwell
    American Journal of Anatomy 132 (1971), S. 61-77 
    Details
    ISSN: 0002-9106
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The appearance and the osmiophilic properties of synthetic dipalmitoyl lecithin (DPL) were characterized under various conditions. It was shown that DPL appeared as 50 Å round to oval dots and lamellae of 50 Å periodicity when negatively stained with phosphotungstate. Osmium-vapor treatment of a DPL suspension produced negatively outlined DPL, similar to the images obtained with negative staining with phosphotungstate. A mixture of ethanol, osmium and DPL showed the heavily osmiophilic lamellae of DPL in thin sections. The periodicity measures 42 Å. These results are the first in the literature to reveal the osmiophilic nature of saturated dipalmitoyl lecithin.Prolonged washing after both glutaraldehyde and osmium fixation of lung tissue, thus eliminating the chance for interaction among osmium tetroxide, ethanol and saturated phospholipid, resulted in a loss of the heavily osmiophilic surface film that has been reported to be present after routine tissue processing. Secondary osmication of the washed lung with a mixture of osmium tetroxide and ethanol solution brought about striking osmiophilia of the surface film, which was lamellar and was identical to synthetic DPL in its periodicity.It is suggested that the osmiophilic line observed after routine tissue processing is saturated phospholipid that binds osmium during the process of ethanol dehydration immediately following osmium fixation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aja.1001320108
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