In vivo induction of O[sup 6]-alkylguanine-DNA-alkyltransferase in response to indium-114m

Journal Article · Fri Apr 01 04:00:00 EST 1994 · Radiation Research; (United States)

DOI:https://doi.org/10.2307/3578843· OSTI ID:6439791

Wilson, R E; Margison, G P; Hoyes, K P; Hendry, J H ^[1]; Morris, I D; Sharma, H L ^[2]

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1. Christie Hospital NHS Trust, Manchester (United Kingdom)
2. Univ. of Manchester (United Kingdom)

The effect of systemic administration of the radionuclide [sup 114m]In on O[sup 6 ]-alkylguanine-DNA-alkyltransferase (ATase) activity has been examined in rats. In response to 14.8 MB/1/kg [sup 114m]In injected intraperitoneally, hepatic ATase was induced maximally approximately fivefold at 7 days after injection, at which time the cumulative radiation dose to the liver was approximately 2 Gy. At 63 days after injection ATase activity was still approximately twofold elevated and remained so at 126 days after injection. By 200 days after injection ATase activity had returned to control values. The [sup 114m]In content of the liver increased to a maximum of 28.7 kBq/g 48-72 h after injection, after which it began to decrease such that at 126 days only 0.3 kBq/g remained and at 200 days 0.03 kBq/g. In response to 4.44 MBq/kg [sup 114m]In, hepatic ATase was induced twofold by 7 days after injection, when the liver had received a radiation dose of 0.6 Gy, and was still slightly elevated at 63 days. There was no ATase induction after 0.44 MBq/kg [sup 114m]In up to 7 days after injection; however, at 42 days after injection activity was approximately twofold higher. These results suggest that induction of hepatic ATase activity by [sup 114m]In is independent upon cumulative radiation dose and dose rate; both must be above minimum threshold values for induction to occur. The induction of a DNA repair enzyme by radiation exposure from an internal radionuclide may have important consequences for risk assessments of occupational, medical and environmental exposures. 36 refs., 3 figs., 3 tabs.

• OSTI ID: 6439791
• Journal Information: Radiation Research; (United States), Journal Name: Radiation Research; (United States) Vol. 138:1; ISSN 0033-7587; ISSN RAREAE
• Country of Publication: United States
• Language: English

Related Subjects

550200 -- Biochemistry
560160* -- Radionuclide Effects
Kinetics
& Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
BODY
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DNA
DNA REPAIR
DOSE-RESPONSE RELATIONSHIPS
ELECTRON CAPTURE RADIOISOTOPES
ENZYME ACTIVITY
ENZYME INDUCTION
ENZYMES
GENE REGULATION
GLANDS
INDIUM 114
INDIUM ISOTOPES
INTERMEDIATE MASS NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
ISOMERIC
ISOTOPES
LIVER
MAMMALS
NUCLEI
NUCLEIC ACIDS
ORGANIC COMPOUNDS
ORGANS
PROTEINS
RADIATION EFFECTS
RADIOISOTOPES
RADIONUCLIDE KINETICS
RATS
REPAIR
RODENTS
TRANSFERASES
VERTEBRATES