Neural, pituitary, and mammary tumors in Sprague-Dawley rats treated with X irradiation to the heat and N-ethyl-N-nitrosourea (ENU) during the early postnatal period: a statistical study of tumor incidence and survival

Journal Article · Fri Mar 01 00:00:00 EST 1985 · Radiat. Res.; (United States)

DOI:https://doi.org/10.2307/3576505· OSTI ID:5612082

Mandybur, T I; Ormsby, I; Samuels, S; Mancardi, G L

To study the late effects of early postnatal treatment with N-ethyl-N-nitrosourea (ENU) preceded by X irradiation to the heat, 226 neonatal CD rats were divided into six groups which received the following treatment: (1) 500-rad X irradiation to the head on the third postnatal day (pnd); (2) injection ip with 30 mg/kg ENU on the fourth pnd; (3) injection ip with 30 mg/kg ENU on the seventh pnd; (4) a combination of 500-rad X irradiation to the head on the third pnd, followed by ip 30 mg/kg ENU on the fourth pnd; (5) a combination of 500-rad X irradiation to the head on the third pnd, followed by ip 30 mg/kg ENU on the seventh pnd; and (6) untreated controls. The results indicate that (1) X irradiation to the head alone significantly extended the life span of females compared to that of control females, and did not affect survival of males; (2) X irradiation did not influence the latent period of mortality from neurogenic tumors when ENU was given 1 or 3 days afterward; (3) ENU itself was a factor in shortening latent period for mammary tumors; (4) X irradiation alone did not increase the incidence of mammary tumors, and revealed no protective effect on the ENU-induced mammary carcinogenesis; (5) X irradiation increased the prevalence of pituitary tumors in the females; (6) no enhancement of pituitary tumors by ENU was observed; and (7) there was a statistically significant association of pituitary and mammary tumors in females.

• Research Organization: Univ. of Cincinnati, OH
• OSTI ID: 5612082
• Journal Information: Radiat. Res.; (United States), Vol. 101:3
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BRAIN
DELAYED RADIATION EFFECTS
MAMMARY GLANDS
MORTALITY
RADIOINDUCTION
NITROSOUREAS
RADIOSENSITIVITY EFFECTS
PITUITARY GLAND
ADENOMAS
CARCINOMAS
EXPERIMENTAL DATA
HEAD
NEONATES
NEOPLASMS
RATS
STATISTICS
X RADIATION
ANIMALS
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BODY
BODY AREAS
CENTRAL NERVOUS SYSTEM
DATA
DISEASES
ELECTROMAGNETIC RADIATION
ENDOCRINE GLANDS
GLANDS
INFORMATION
IONIZING RADIATIONS
MAMMALS
MATHEMATICS
NERVOUS SYSTEM
NITROSO COMPOUNDS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
RADIATION EFFECTS
RADIATIONS
RODENTS
VERTEBRATES
560152* - Radiation Effects on Animals- Animals