Bronchi, human

If a-hydroxylation of NPYR is its mechanism of activation, one would expect the formation of carcinogen-DNA adducts containing a 4-oxobutyl- or related residue. Adducts have been isolated from the liver RNA of NPYR treated rats, but their structures have not been determined (25). Carcinogen DNA adducts have also been isolated from cultured human esophagus, colon, and bronchus (26, 27, 28). 

In addition to this major adduct which, in some biological systems, such as human bronchus (90) or mouse skin (74) or fibroblast 10T1/2 cells in culture (133), accounts for almost all of the DNA adducts, other derivatives have been detected in many systems which have been investigated. These may vary with respect to tissue (134.135.136) or time of exposure (135,137). 

Respiratory Effects. Intra-alveolar bleeding, edema of the lungs, and blood in the bronchus were observed at autopsy in a man who had been dead for at least 24 hours after ingesting an unknown quantity of disulfoton (Hattori et al. 1982). This was the only information found regarding respiratory effects in humans after oral exposure to disulfoton. 

McDowell EM, Barrett LA, Glavin F, Harris CC, Trump BF (1978) The respiratory epithelium. I. Human bronchus. J Natl Cancer Inst 61(2) 539-549. 

There have been a number of studies of the thickness and velocity of the mucus layer, with different results. Dalham reported a thickness of 5 Min in the trachea of rats. Similarly, Alder et al. reported 10 Mm and less in cats, and Comroe reported 10-15 urn. Velocity has been measured at 13.5 mm/min in rats, 0-35 mm/min in cows and 5-14 mm/min in dogs, 10.5 3.7 mm/min in cats, and 15 mm/min in the human trachea and 3.75 mm/min in the human main bronchus. ... 

Fig. 3.1 Schematic diagram of the human respiratory system. The gross anatomy of the lung, the covering membranes (pleura), airways and air sacs (alveoli) are shown. The average diameter of portions of the air flow system are indicated trachea, 20 mm bronchus, 8 mm terminal and respiratory bronchioles, 0.5 mnn alveolar duct, 0.2 mm alveolar sacs, 0.3 mm.

Autrup, H., C. C. Harris, G. D. Itmer, J. K. Selkirk, P. M. Scafer, and B. F. Trump (1978). Metabolism of [ H] bezo(a)p)frene by cultured human bronchus and cultured human pulmonary alveolar macrophages. Lab. Invest. 38 217-224. 

Marthan, R, Martin, C., Amedee, T. and Mironneau, J. (1989) Qdcium channel currents in isolated smooth muscle cells from human bronchus. J. Appl. Physiol. 66, 1706-1714. 

Plate I (a) Visualization of normai human bronchus by fibreoptic bronchoscopy, (b) Corresponding image from a patient with miid allergic asthma showing evidence of mucosal inflammation after initiation of a iocai response... 

HeLa cel 1s/unscheduled DNA synthesis Human bronchus cells Hamster embryo cells Hamster embryo cells/... 

Richmond I, Pritchard GE, Ashcroft T, et al. Bronchus associated lymphoid tissue (BALT) in human lungs Its distribution in smokers and nonsmokers. Thorax. 1993 48 1130-1134. 

CHRONIC HEALTH RISKS pneumoconiosis (dust in the lungs) emphysema bronchitis lesions of the respiratory and digestive systems increase in cancer of the lungs, kidney, trachea, bronchus, and prostrate severe dermatitis skin lesions disfiguring pigmentation of the skin conjunctivitis other skin disorders such as folliculitis, furunculosis, erythema, photosensitivity, melanosis, and warts EPA Group A classifiable as a human carcinogen. 

Neuropeptide y (NPy), DAGHGQISHK RHKTDSFVGL Ma, a member of the mammalian tachykinins. NPy is encoded on the prepro-tachykinin gene TACl. The differential inclusion or exclusion of exon 4 into y and fiTACl allows the formation of two extended NKA peptides, either NPy or neuropeptide K. NPy was discovered in an extract of the rabbit intestinal tract. It corresponds to y-prepro-tachykinin-(72-92). NPy has been reported to be the most potent contractile tachykinin in human isolated bronchus, acting through a non-classical NK2 receptor [R. Kage et al., J. Neurochem. 1988, 50, 1412 E. Burcher et al.. Neuropeptides 1991, 20, 79]. 

Human perfused lung trachea Bronchus HPLC... 

In studies with both hamster and human lung short-term cultures, major metabolites of BaP included the 9,10-dihydrodiol, the 7,8-dihydrodiol, and the sulfate conjugate of 3-hydroxy-BaP (78, 80, 81). Glucuronides of 3-hydroxy-BaP and the 7,8- and 4,5-dihydrodiols were also detected. The 7,8-dihydrodiol was active in binding to DNA of cultured hamster lung and cultured human bronchus (81, 503). Metabolic studies with the (-)-7,8-dihydrodiol in cultured human bronchus indicated that it was converted to the 7,8-dihydrodiol-9,10-epoxide (isomer I) which bound to DNA to give the major adduct 5 (Fig. 4) (503). The results of these studies indicate similarities in the metabolic activation of BaP in rodents and man. 

The metabolism and binding to DNA of BaP has also been studied in cultured human colon and esophagus (16, 179). Metabolites included the 7,8- and 9,10-dihydrodiols, 7,8,9,10-tetraols, and conjugates. The relative distribution of metabolites varied among individuals. The major DNA adduct was 5 (Fig. 4). Thus, the metabolic pathways and activation of BaP were similar in bronchus, esophagus, and colon. 

Soybean lipoxygenase-1 also acts as a 15-lipoxygenase for AA, but the amino acid identity between human 15-lipoxygenase and the soybean enzyme is only 22% [77]. cDNA encoding 15-lipoxygenase cloned from human bronchus cDNA library [78] is identical with that from human reticulocyte cDNA library [77]. Thus the presence of two forms of 15-lipoxygenase in a human leucocyte preparation [82] awaits further investigation. 

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