Immediate dose-rate effects of /sup 60/Co on performance and blood pressure in monkeys

Journal Article · Sun May 01 04:00:00 EDT 1977 · Radiat. Res.; (United States)

DOI:https://doi.org/10.2307/3574595· OSTI ID:7215286

Bruner, A

Four groups of monkeys received 1000 rad of /sup 60/Co at 33, 50, 75, or 180 rad/min whole-body irradiation while performing a delayed matching-to-sample task. Systematic dose-rate effects were observed on performance and blood pressure within the initial 20 min postirradiation. The incidence and severity of performance decrement increased with higher dose rate. The incidence of performance decrement was 7, 33, 33, and 81%, respectively, for the 33, 50, 75, and 180 rad/min groups, including those animals showing early transient incapacitation. The appearance of postirradiation hypotension was systematically delayed and its rate of fall prolonged as dose rate was lower. The hypotension likewise appeared less deep with lower dose rate. Based on the calculated cumulative dose absorbed at the time of symptom appearance, two coactive thresholds were proposed to exist: a total dose threshold of approximately 300 rad and a dose-rate threshold of about 25 rad/min, for the induction of the early hypotension-performance decrement syndrome. Performance decrement occurred only in the presence of hypotension, usually following its nadir by 1 to 4 min. Moreover, an increasing strength of association between depth of hypotension and frequency of decrement was demonstrated as the hypotension declined below 50% of baseline.

• Research Organization: Lovelace Foundation for Medical Education and Research, Albuquerque, NM
• OSTI ID: 7215286
• Journal Information: Radiat. Res.; (United States), Journal Name: Radiat. Res.; (United States) Vol. 70:2; ISSN RAREA
• 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.
ANIMALS
BEHAVIOR
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BLOOD PRESSURE
COBALT 60
COBALT ISOTOPES
DOSE RATES
DOSE-RESPONSE RELATIONSHIPS
DOSES
ELECTROMAGNETIC RADIATION
GAMMA RADIATION
INTERMEDIATE MASS NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
IONIZING RADIATIONS
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MAMMALS
MINUTES LIVING RADIOISOTOPES
MONKEYS
NUCLEI
ODD-ODD NUCLEI
PRIMATES
RADIATION DOSES
RADIATION EFFECTS
RADIATIONS
RADIOISOTOPES
VERTEBRATES
YEARS LIVING RADIOISOTOPES