Mammary carcinogenic effect of low-dose fission radiation in Wistar/Furth rats and its dependency on prolactin

Journal Article · Sun Jun 01 04:00:00 EDT 1980 · J. Natl. Cancer Inst.; (United States)

OSTI ID:5179225

Yokoro, K ^[1]; Sumi, C; Ito, A; Hamada, K; Kanda, K; Kobayashi, T

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1. Hiroshima Univ., Japan

The mammary carcinogenic effect in rats of low-dose fission radiation and its dependency on prolactin were studied. A total of 141 female W/Fu rats were exposed to 4.8, 8.9, or 19.5 rads of fission radiation that had both fission neutrons of 2.0 million electron volts (MeV) and gamma ray components similar to those produced by the Hiroshima bomb. Only 1 of 48 rats (2.0%) developed mammary tumor (MT) after irradiation alone, whereas 20 of 48 rats (41.6%) developed MT's if prolactin was supplied shortly after irradiation by means of grafting of the prolactin-secreting pituitary tumor. Furthermore, MT's occurred in 11 of 45 rats (24.4%) treated wit prolactin as late as 12 months after irradiation, which suggested the long-term survival of radiation-induced dormant MT cells. A correlation was found between the development of MT and the elevation of serum prolactin level; most MT's appeared shortly after the grafted mammotropic pituitary tumor became palpable. The growth of MT's appeared to be promoted by prolactin in collaboration with ovarian hormones; the growth of adenocarcinomas was dependent on prolactin and ovarian hormones, whereas the growth of fibroadenomas appeared to be less hormone-dependent. Much higher bioiogic effectiveness, especially in the low-dose range, was found with 2.0-MeV fission neutrons compared with 14.1-MeV fast neutrons or 180-kilovolt peak X-rays in rat mammary carcinogenesis.

• OSTI ID: 5179225
• Journal Information: J. Natl. Cancer Inst.; (United States), Journal Name: J. Natl. Cancer Inst.; (United States) Vol. 64:6; ISSN JNCIA
• Country of Publication: United States
• Language: English

Related Subjects

560152* -- Radiation Effects on Animals-- Animals
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ADENOMAS
ANIMALS
BARYONS
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BODY
CARCINOGENESIS
CARCINOMAS
COMPARATIVE EVALUATIONS
DISEASES
DOSES
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
FAST NEUTRONS
FERMIONS
FISSION NEUTRONS
FISSION PRODUCTS
GAMMA RADIATION
GLANDS
GONADOTROPINS
GRAFTS
HADRONS
HORMONES
IONIZING RADIATIONS
IRRADIATION
ISOTOPES
LOW DOSE IRRADIATION
LTH
MAMMALS
MAMMARY GLANDS
NEOPLASMS
NEUTRONS
NUCLEONS
ORGANS
PATHOGENESIS
PEPTIDE HORMONES
PITUITARY HORMONES
RADIATION DOSES
RADIATION EFFECTS
RADIATIONS
RADIOACTIVE MATERIALS
RADIOINDUCTION
RADIOSENSITIVITY EFFECTS
RATS
RBE
RESPONSE MODIFYING FACTORS
RODENTS
TRANSPLANTS
VERTEBRATES