Effect Of Excess Iodide On The Structure Of Thyroid Gland Of Growing Male Albino Rats

Iodine excess is associated with a spectrum of thyroidal effects. Therefore, the present study was conducted to assess the effects of excess potassium iodide (KI) on histological and immunohistochemical structure of thyroid gland. Also, to assess the biochemical changes in serum thyroid hormones and serum TSH. For this purpose, fourty healthy growing male albino rats aging (4-6 weeks) were used in this study. The animals were classified into two equal groups: Control group, in which the animals were given distilled water without iodide and KI treated group, in which the animals were given 0.1 mg/kg B.W KI/day dissolved in distilled water and given by oral gavage for four and eight weeks. Examination of thyroid sections in KI treated group showed enlarged follicular cavities, colloidal vacuolations and most of the follicles were lined by flattened follicular cells with flattened nuclei. Also, the cytoplasm of follicular cells showed dilatation of cisternae