Influence of x irradiation and diet on pituitary/thyroid function in the rat

Thesis/Dissertation · Mon Jan 01 04:00:00 EST 1979

DOI:https://doi.org/10.2172/6136338· OSTI ID:6136338

Qassar, Iyad G. ^[1]

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1. Univ. of Rochester, NY (United States)

Rats were maintained on low iodine diet or treated with T₄. A significant increase in thyroid weight was observed in rats on low iodine diet whereas among rats on normal diet with thyroxine injections, the thyroid was lower in weight than thyroids of control animals. Pituitary weight increased significantly in rats on low iodine diet or T₄ treatment. Labelling index was significantly higher in the group on low iodine diet. A significantly lower labelling index was observed after thyroxine treatment. Where PTU was administered to rats pretreated with either normal diet, normal diet plus T₄, or maintained on low iodine diet and then exposed to radiation (100 to 400R) to the neck, it was not possible to distinguish the effect of such local radiation on body growth. The pre-radiation treatment did not have any effect on thyroid weight during two weeks post-radiation, suggesting that a four week post-radiation period is essential to elicit radiation effects on the thyroid. Contrary to low iodine treatment, administration of PTU did not result in any increase in pituitary weight in rats maintained on normal diet prior to radiation or in rats maintained on low iodine diet prior to radiation. There was, however, a significant increase in pituitary weight in rats injected with thyroxine prior to radiation (250R or 400R). A significant increase in serum TSH was observed two weeks after radiation and PTU treatment. A lower TSH level was observed, however, in the 250R sub-group (normal diet or T₄ injection) and in the 400R sub-group (low iodine diet). There was a significant difference among sham-irradiated and the three x-irradiated sub-groups maintained on low iodine diet. The results of these studies indicate that local x irradiation with 100 to 400R to the neck may influence thyroid/pituitary function in the rat. (ERB)

• Research Organization: Univ. of Rochester, NY (United States). Dept. of Radiation Biology and Biophysics
• Sponsoring Organization: USDOE
• DOE Contract Number: EY-76-C-02-3490
• OSTI ID: 6136338
• Report Number(s): UR--3490-1674
• Country of Publication: United States
• Language: English

Related Subjects

550901 -- Pathology-- Tracer Techniques
551001 -- Physiological Systems-- Tracer Techniques
560152* -- Radiation Effects on Animals-- Animals
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMINO ACIDS
ANIMALS
ANTITHYROID DRUGS
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BODY
BODY AREAS
CARBOXYLIC ACIDS
DATA
DATA FORMS
DIET
DRUGS
ELECTROMAGNETIC RADIATION
ELEMENTS
ENDOCRINE GLANDS
EXPERIMENTAL DATA
GLANDS
HALOGENS
HORMONES
INFORMATION
IODINE
IONIZING RADIATIONS
IRRADIATION
ISOLATED VALUES
LOCAL IRRADIATION
LOW DOSE IRRADIATION
MAMMALS
NECK
NONMETALS
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
ORGANS
PEPTIDE HORMONES
PITUITARY GLAND
RADIATION EFFECTS
RADIATIONS
RADIOSENSITIVITY EFFECTS
RATS
RODENTS
THYROID
THYROID HORMONES
THYROXINE
VERTEBRATES
X RADIATION