Metabolism of [3H]benzo[a]pyrene by cultured human bronchus and cultured human pulmonary alveolar macrophages

Autrup, H; Harris, CC; Stoner, GD; Selkirk, JK; Schafer, PW; Trump, BF

HERO ID

59970

Reference Type

Journal Article

Year

1978

Language

English

PMID

633846

HERO ID 59970
In Press No
Year 1978
Title Metabolism of [3H]benzo[a]pyrene by cultured human bronchus and cultured human pulmonary alveolar macrophages
Authors Autrup, H; Harris, CC; Stoner, GD; Selkirk, JK; Schafer, PW; Trump, BF
Journal Laboratory Investigation
Volume 38
Issue 3
Page Numbers 217-224
Abstract HEEP COPYRIGHT: BIOL ABS. The metabolism of the carcinogen (3H)benzo(a)pyrene by cultured human bronchial epithelium and cultured pulmonary alveolar macrophages from the same donor was studied. Explants of bronchus were prepared from surgical and autopsy specimens, and human pulmonary alveolar macrophages were isolated from peripheral lung by trypsinization and differential adhesion to plastic tissue culture dishes. After 7 days in culture the bronchus explant and pulmonary alveolar macrophages were exposed to (3H)benzo(a)pyrene, and binding to cellular macromolecules was studied. Aryl hydrocarbon hydroxylase activity was determined by the release of 3H water into the culture medium from metabolized (3H)benzo(a)pyrene. Variation in the binding level of benzo(a)pyrene to DNA and protein in pulmonary alveolar macrophages from different individuals showed 9- and 33-fold interindividual variation, respectively. The metabolism of benzo(a)pyrene was further investigated in macrophages. Binding of benzo(a)pyrene to macromolecules and aryl hydrocarbon hydroxylase activity were dependent on the length of time the explant was in culture and length of exposure to benzo(a)pyrene. Pretreatment of macrophages with benz(a)anthracene increased the binding level of benzo(a)pyrene and aryl hydrocarbon hydroxylase activity. When coincubated with benzo(a)pyrene, cycloheximide, 7,8-benzoflavone or actinomycin D reduced both the level of binding and activity of aryl hydrocarbon hydroxylase. When macrophage cultures were maintained at pO2 greater than atmospheric air, an increase in binding level and enzyme activity was found. The major metabolites of benzo(a)pyrene formed by macrophages were 7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene, (5-25% of total metabolites) 9,10-dihydroxy-9,10-dihydrobenzo(a)pyrene (16-39%) and 2 distinct peaks containing unidentified polar metabolites. A negative correction (r = -0.58; P 0.05) between binding of benzo(a)pyrene to protein and aryl hydrocarbon hydroxylase exists in pulmonary macrophages, but no correlation between data from bronchus and macrophages was found.
Pmid 633846
Is Certified Translation No
Dupe Override 59970
Comments 3 in title is a superscript.Lab. Invest. 38: 217-224.
Is Public Yes
Language Text English
Is Qa No