Radioautographic measurement of electron-induced epidermal kinetic effects in different aged rats

Journal Article · Sun Mar 01 00:00:00 EST 1987 · J. Invest. Dermatol.; (United States)

DOI:https://doi.org/10.1111/1523-1747.ep12466199· OSTI ID:6571775

Sargent, E V; Burns, F J

We have previously shown that the ability of rat epidermal cells to repair electron-induced DNA damage decreases as a function of age. The present investigation was performed to examine the relationship between this finding and sensitivity of epidermal cells to the cytotoxic effects of the radiation. Male CD rats at ages 2, 28, 100, 200, 420, and 728 days were injected with (/sup 3/H)-thymidine (( /sup 3/H)Thd) at a dose of 2 mu Ci/g body weight. One hour later, the rats were anesthetized and the dorsal skin irradiated with various doses of 0.8 meV electrons at a dose rate of 660 rads/min. At 24 h after irradiation, radioautographs were made of a sheet of epidermis that was separated by trypsinization from the underlying dermis. Labeled cells were scored either as singlets or doublets (adjacent labeled cells). The percent labeled cells and percent labeled cells as doublets were determined. The estimated labeling index (the proportion of cells labeled by a single exposure to (/sup 3/H)Thd) of the epidermal basal layer decreased as a function of age. The slope of the semilog plot of the percent labeled cells as doublets as a function of electron dose indicates that the Do value decreases with increasing age. The results show, however, that the greatest difference in sensitivity occurs between 2-day (neonatal) and 28-day (pubescent) animals and again between 420-day (adult) and 728-day (senescent) animals.

• Research Organization: New York Univ. Medical Center, NY
• OSTI ID: 6571775
• Journal Information: J. Invest. Dermatol.; (United States), Vol. 3
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
EPIDERMIS
BIOLOGICAL RADIATION EFFECTS
RADIOSENSITIVITY
AGE DEPENDENCE
AGING
AUTORADIOGRAPHY
CELL CYCLE
ELECTRONS
RADIATION DOSES
RATS
THYMIDINE
TRITIUM COMPOUNDS
ANIMAL TISSUES
ANIMALS
AZINES
BIOLOGICAL EFFECTS
BODY
DOSES
ELEMENTARY PARTICLES
EPITHELIUM
FERMIONS
HETEROCYCLIC COMPOUNDS
LABELLED COMPOUNDS
LEPTONS
MAMMALS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PYRIMIDINES
RADIATION EFFECTS
RIBOSIDES
RODENTS
SKIN
TISSUES
VERTEBRATES
560152* - Radiation Effects on Animals- Animals