A method for in vitro culture of rat Zymbal gland: Use in mechanistic studies of benzene carcinogenesis in combination with sup 32 P-postlabeling
- Mobil Oil Corporation, Princeton, NJ (USA)
Zymbal glands were excised bilaterally from the ear ducts of female Sprague-Dawley rats (three/group), minced into approximately four fragments per gland, and transferred into a microtiter plate containing 1.5 mL per well of Waymouth's tissue culture medium supplemented with fetal calf serum, hydrocortisone, insulin, and gentamicin. After addition of a test compound or solvent vehicle, plates were incubated for 6, 24, 48, or 96 hr at 37 degrees C in a humidified atmosphere of 5% CO2 in air. Tissue in culture for 6 hr was histologically indistinguishable from the freshly excised tissue, while that in culture for 24, 48, and 96 hr showed a progressive deterioration often with necrosis and/or squamous metaplasia. More pronounced deterioration was noted in samples treated with 750 or 1500 micrograms/mL of benzene. Using a nuclease P1-enhanced 32P-postlabeling assay, aromatic DNA adducts were detected in cultured Zymbal glands exposed for 48 hr to benzene and its derivatives, as well as to 7,12-dimethylbenzanthracene (DMBA) and 2-acetylaminofluorene (AAF). Benzene produced very low levels of adducts (0.5 adducts per 10(9) nucleotides), whereas its congeners produced relatively high levels of adducts (50-2000 lesions per 10(9) nucleotides), which decreased in the order benzoquinone greater than hydroquinone greater than phenol greater than benzenetriol greater than catechol. Each adduct profile overall was characteristic for the compound studied, suggesting the formation of compound-specific electrophiles. AAF and DMBA adducts were identical to those formed in vivo in animals. Our results show that the Zymbal glands are capable of metabolizing different carcinogens to DNA-reactive intermediates, a process that may be causally associated with tumor formation in vivo in this organ.
- OSTI ID:
- 5256441
- Journal Information:
- Environmental Health Perspectives; (USA), Vol. 82; ISSN 0091-6765
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
59 BASIC BIOLOGICAL SCIENCES
ACETYLAMINOFLUORENES
TOXICITY
BENZANTHRACENE
BENZENE
AUDITORY ORGANS
CARCINOGENESIS
DNA ADDUCTS
METABOLIC ACTIVATION
PHOSPHORUS 32
QUINONES
RATS
TISSUE CULTURES
TRACER TECHNIQUES
ADDUCTS
ANIMALS
AROMATICS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
CONDENSED AROMATICS
DAYS LIVING RADIOISOTOPES
HYDROCARBONS
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
MAMMALS
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
ORGANS
PATHOGENESIS
PHOSPHORUS ISOTOPES
RADIOISOTOPES
RODENTS
SENSE ORGANS
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology
550501 - Metabolism- Tracer Techniques