Inhibition of benzo(a)pyrene-induced mammary carcinogenesis by retinyl acetate. [Rats]
The administration of a 250-ppM retinyl acetate dietary supplement for various periods relative to intragastric administration of 50 mg benzo(a)pyrene (BP) significantly inhibited the induction of mammary cancers in virgin female inbred LEW/Mai rats. With day of BP administration taken as time 0, groups receiving the retinoid from weeks -2 to +1, +1 to +90, +20 to +90, and -2 to +90 showed a significant reduction in tumor response as compared to controls. The inhibition of carcinogenesis achieved by a +1 to +20 administration schedule was temporary. A 2-week exposure to supplemental retinyl acetate significantly reduced the mammary gland parenchymal cell labeling index in ductal, alveolar, and terminal end bud structures. Beginning the retinyl acetate supplement 1 week after the administration of BP significantly reduced the number of terminal ductal hyperplasias. The inhibition of carcinogenesis achieved by a short period of retinyl acetate administration before and during the period of carcinogen availability as well as the inhibition achieved by long-term postcarcinogen retinoid exposure may involve an antiproliferative effect on the rat mammary gland.
- Research Organization:
- New York Univ., NY
- DOE Contract Number:
- EY-76-S-02-2737
- OSTI ID:
- 6495666
- Journal Information:
- J. Natl. Cancer Inst.; (United States), Vol. 66:3
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
BENZOPYRENE
CARCINOGENESIS
INHIBITION
VITAMIN A
BIOLOGICAL EFFECTS
FEMALES
MAMMARY GLANDS
ORAL ADMINISTRATION
RATS
ANIMALS
AROMATICS
BODY
CONDENSED AROMATICS
GLANDS
HYDROCARBONS
MAMMALS
ORGANIC COMPOUNDS
ORGANS
PATHOGENESIS
RODENTS
VERTEBRATES
VITAMINS
560305* - Chemicals Metabolism & Toxicology- Vertebrates- (-1987)