The interference of excessive bromide intake with iodine metabolism in the rat was studied using 82Br and 131I radionuclides. Mainly lactating rat dams and their pups were used, in addition to adult male rats, in the present studies.
Particularly, the influence of high bromide intake in lactating rat dams on the transfer of iodine and bromide to suckling
young through breast milk was evaluated. The induction of hypothyroid status in the pups by high bromide intake in the mothers
was proved unambiguously. Excessive bromide in lactating rat dams caused a marked decrease in plasma levels of thyroid hormones
both, in the mothers and in their sucklings. The effects of an enhanced bromide intake on the thyroid function in relation
to iodine status in the animals were also followed. Marked goitrogenic and thyrotoxic effects of excessive bromide in adult
rats were significantly enhanced under the conditions of simultaneous iodine deficiency in the experimental animals.
Authors:A. Fekry, N. El-Bieh, K. Elwan, and S. Mangood
This study was carried out to verify the therapeutic role of Prussian Blue (PB) in removing internal [137Cs] contamination from rats and to evaluate any side effects caused by chronic consumption of this compound on hematological (RBCs, Hb) parameters, serum biochemical contents (total proteins, albumin, globulins, A/G ratio, urea, urea nitrogen, creatinine, cholesterol, calcium, sALT and sAST enzymatic activity, bilirubin) and thyroid function (T4 and T3). PB administration before or at the time of irradiation could eliminate the decreased or increased effects of [137Cs]-gamma irradiation on: RBCs, Hb, total proteins, globulins, creatinine, urea, urea nitrogen, SAT, T3, T4. However, PB administration, one or seven days post irradiation eliminated [137Cs]-gamma irradiation effects on: cholesterol, calcium, bilirubin in both of growing and adult rats.
Authors:Shen Rongsen, Wang Renzhi, Xing Ruiyun, Li Yingoi, Zhou Fengqi, Jiang Shaohua, Lin Zhihao, and Xu Banglei
Three types of magnetic microparticle antibodies were developed: 1) magnetic second antibody I (MSA-I) where the antibody molecules were directly immobilized by physical adsorption on Fe3O4 microparticles (magnetic nucleus, MN) 10nm±34% in diameter, 2) magnetic second antibody II (MSA-II) where the antibody molecules were immobilized by chemical coupling on the MN coated with polyacrolein, and 3) magnetic, first antibody (MFA-T3) where the anti-T3 antibody molecules were specifically immobilized by immunoadsorption to the second antibody molecules of the MSA-II. The optimal conditions for their preparation were elaborated. Some physical, chemical and immunological characteristics of these magnetic microparticles were described. The application of the MSA-I, MSA-II and MFA-T3 to RIAs for evaluation of thyroid function, such as triiodothyronine (T3), reverse T3(rT3), free T3 (fT3), thyroxine (T4), free T4(fT4), thyroid-stimulating hormone (TSH), thyroglobulin (TG) and TG-antibody (TG-Ab), etc., was reported.
Thirty radioisotopes of iodine are known but only those with mass numbers from 123 to 135 are of major radiotoxicological
interest. Exposure of animals or man to inorganic131I or125 I may result in the induction of benign or malignant thyroid tumors or depression of thyroid function; Bq for Bq125I is less toxic than131I. However, the shorter lived radioiodines132I,133I, and135I appear to be 10 to 100 X more toxic than131I alone. Adrenal, pituitary and ovarian tumours, as well as parathyroid hypofunction and other biochemical disturbances, have
been reported in animals but not, so far, in man. Gonad doses from131I up to at least 800 mGy do not appear to cause in man an increased incidence of congenital abnormalities or spontaneous abortions.
Little information is available about the toxicity of radioiodine containing organic compounds. The DNA precursor, iododeoxyuridine
when labelled with125I becomes incorporated into the cell nucleus and produces severe and often irreparable damage due to the emission of Auger
electrons. The risk estimate for the induction of thyroid carcinoma or adenoma by inorganic131I is considered to be 10 to 20·10−6 persons Gy−1 y−1, but may be up to 100 times larger for persons exposed to mixtures of short-lived radioiodines.
Bloom , M , Spliethoff , H , Vena , J , Shaver , S , Addink , R , Eadon , G . Environmental exposure to PBDEs and thyroidfunction among New York Anglers . Environ Toxicol Pharm . 2008 ; 25 : 386 – 392