文档介绍：1 碘缺乏和碘过量对大鼠心肌组织结构和电活动的影响作者: 刘桂芝, 张朝, 吴逸明, 叶振坤, 陈祖培, 阎玉芹【关键词】碘;甲状腺功能减退症;心电图;组织学 Effects of iodine deficiency and iodine excess on rat myocardial histology and electrical activity 【 Abstract 】 AIM: To observe the effects of iodine deficiency and iodine excess on rat myocardial histology and electrical activity. METHODS: y Wistar rats were divided into 6 groups at random: low iodine (LI), normal iodine (NI), 5fold iodine (5HI), 10fold iodine (10HI), 50fold iodine (50HI) and 100fold iodine group (100HI) respectively and all fed with water containing various concentrations of KIO3. At3 and 6 months after iodine administration, the median of urinary iodine was measured. At6 months after iodine administration, the level of thyroid hormone (TH) in serum was measured by means of 2 chemoluminescence. The electrocardiogram (ECG), the heart wEight to body wEIght ratio (H/B ratio) were recorded. The histopathological changes of left ventricular myocardium were observed with light microscope. RESULTS: pared with NI groups, the median of urinary iodine and the level of serum TH were decreased ( ) whereas H/B ratio was increased in LI group ( ). The pathological changes of left ventricle were the increased inner diameter of left ventricular cavity, the decreased thickness of left ventricular free wall and the local necrosis. In response to various iodine treatment, the level of urinary iodine rose significantly with increasing concentration of iodine. Although the level of serum TH was not significantly changed in each iodine treatment group, there was a strong decreasing trend for serum TH among HI groups. The levels of TT3 declined in 10HI [ ( ± ) nmol/L ], 50HI [ ( ± ) nmol/L ] and 100HI [ ( ± ) nmol/L ] pared with NI[ ( ± ) nmol/L ] group ( , and , respectively ). The levels of TT4 went down only in 10HI [ ( ± ) nmol/L ] and 50HI [ ( ± ) nmol/L ] pared with NI group [ ( ± ) nmol/L ] (