title: Calcium iodate-another effective blocker of radioiodine uptake by the thyroid gland.
abstract: KI and KIO3 are the commonly used prophylactic drugs for the protection of thyroid glands against radioiodine. In this study, we have demonstrated the use of another iodine containing salt, calcium iodate [Ca(IO3)2], as an effective blocker of radioiodine uptake by the thyroid gland in rats. Ca(IO3)2 is permitted by the FDA as a food additive and is "generally regarded as safe" (GRAS, CFR No.1206). We have also compared the efficacy of Ca(IO3)2 with KIO3 in blocking thyroidal uptake of radioiodine, which could be important considering the better shelf life of Ca(IO3)2. Laboratory rats were administered 131I and stable iodide in the form of KIO3 or Ca(IO3)2 was given orally, 2 h after the administration of 131I. All the animals were monitored for whole body retention (WBR) of 131I, at 24 h and further for 14 d. The results of the present study provide us with evidence that Ca(IO3)2 can serve as another promising radioiodine blocker, and is as equipotent as KI/KIO3 in protecting the thyroid gland. We have not found any studies that examined the property of Ca(IO3)2 in blocking radioiodine uptake by the thyroid gland and the present study is an attempt in this direction.
authors.affiliation: Laboratory Nuclear Medicine Section (Isotope Group, B.A.R.C.), Tata Memorial Hospital Annexe, Bhabba Atomic Research Center, Parel, Mumbai 400 012, India. palpahuja@yahoo.co.in
authors.forename: D N
authors.initials: DN
authors.lastname: Pahuja
authors.forename: V S
authors.initials: VS
authors.lastname: Jagtap
authors.forename: V R
authors.initials: VR
authors.lastname: Sonawane
authors.forename: M G R
authors.initials: MG
authors.lastname: Rajan
authors.forename: A M
authors.initials: AM
authors.lastname: Samuel
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001822:Body Burden; D002118:Calcium / Q000008:administration & dosage; D007452:Iodates / Q000008:administration & dosage*; D007457:Iodine Radioisotopes / Q000032:analysis* / Q000493:pharmacokinetics*; D008657:Metabolic Clearance Rate / Q000187:drug effects; D009928:Organ Specificity; D011829:Radiation Dosage; D011832:Radiation Injuries / Q000517:prevention & control*; D011835:Radiation Protection / Q000379:methods*; D011836:Radiation Tolerance / Q000187:drug effects; D011837:Radiation-Protective Agents / Q000008:administration & dosage*; D011874:Radiometry; D019275:Radiopharmaceuticals / Q000032:analysis / Q000493:pharmacokinetics; D051381:Rats; D017208:Rats, Wistar; D013961:Thyroid Gland / Q000187:drug effects* / Q000378:metabolism*; D014018:Tissue Distribution / Q000187:drug effects; D014915:Whole-Body Counting
chemical_list: D007452:Iodates; D007457:Iodine Radioisotopes; D011837:Radiation-Protective Agents; D019275:Radiopharmaceuticals; D002118:Calcium