摘要
目的研究L-3，5-二碘酪氨酸（DIT）和碘酸钾（K103）对缺碘大鼠的补碘效果。方法取60只体质量为160～180g的Wistar大鼠，按体质量采用随机数字表法分为缺碘模型组和适碘模型组。缺碘模型组大鼠40只，饲以低碘饲料（碘含量为35．9μg／kg）；适碘模型组大鼠20只，饲以低碘饲料的同时每天灌胃含K103（碘含量为18mg／L）水0．5ml。模型建立时间为3个月。缺碘模型组大鼠再分为3组：低碘（U）组（8只）、KIO，组（9只）、DIT组（10只）；适碘模型组取9只大鼠作为适碘对照（NI）组。u组饲以低碘饲料；KIO3组饲以低碘饲料的同时每天灌胃含KIO3（碘含量为18mg／L）水0．5ml；DIT组饲以低碘饲料的同时每天灌胃含DIT（碘含量为18mg／L）水0．5ml；NI组饲以低碘饲料的同时每天灌胃含K103（碘含量为18mg／L）水0．5ml。3个月后，收集各组大鼠24h尿样，尿中碘的砷铈催化分光光度法（WS／T107—2006）检测尿碘；25％乌拉坦腹腔注射麻醉大鼠，腹主动脉采血，全自动电化学发光免疫分析法测定大鼠血清甲状腺激素[三碘甲状腺原氨酸（TT3）、游离三碘甲状腺原氨酸（FT，）、甲状腺素（n）、游离甲状腺素（n）]水平；处死大鼠，称量甲状腺重量。结果①4组大鼠尿碘含量比较差异有统计学意义（x2=25．24，P〈0．05），其中LI组尿碘中位数明显低于NI、K103和DIT组（3．00比286．14、223．37、214．33肛g／L，P均〈0．05）。（至）4组大鼠血清TT3、TT4、FT3、FT4含量比较差异有统计学意义（F=63．48、140．73、130．20、365．27，P均〈0．05），其中K103组大鼠各激素水平低于DIT组[TT3：（1．57±O．20）比（1．97±0．18）mmol／L、TT4：（51．23±4．90）比（71．94±5．27）mmol／L、FT3：（5．34±0．45）比（6．98±0．33）pmol／L、FT4（26．18±2．30）比（35．47±2．28）pmol／L，P均〈0．05]。KIO3和DIT组大鼠甲状腺均呈淡粉色；4组大鼠甲状腺绝对重量、相对重量比较差异均有统计学意义（F=225．05、345．40，P均〈0．05），其中DIT组大鼠甲状腺绝对重量[（31．76±1．75）mg]和相对重量[（11．69±3．47）mg／100g]均低于K103组[（36．31±5．23）mg、（12．83±4．38）mg／100g，P均〈0．05]。结论动物实验结果显示DIT的补碘效果优于K103。
Objective To study the efficacy of L-3,5-diiodotyrosine （DIT） and inorganic iodine （KIO3） in iodine-deficiency Wistar rats. Methods Sixty Wistar rats, weighting about 160 - 180 g, were divided into two groups according to body weight by the random number table method： iodine-deficiency model （40 rats） was fed with low-iodine food （the iodine content was 35.9 μg/kg）; optimal-iodine model （20 rats） was fed with low-iodine food and given with KIO3 water （the iodine content was 18 mg/L） 0.5 ml by intragastric once a day. Model was established for 3 months. Iodine-deficiency model was subdivided into low iodine （LI） group, KIO3 group and DIT group, eight, nine, ten rats in each group; from optimal-iodine model, nine rats were randomly selected as optimal iodine （NI） group. LI group was fed with low-iodine food; KIO3 group was fed with low-iodine food and given with KIO3 water （the iodine content was 18 mg/L） 0.5 ml by intragastric once a day; DIT group was fed with low-iodine food and given with DIT water （the iodine content was 18 mg/L） 0.5 ml by intragastric once a day; NI group was fed with low-iodine food and given with KIO3 water （the iodine content was 18 mg/L） 0.5 ml by intragastric once a day. After 3 months, 24-hour urine of the rats was collected. According to the method for determination of iodine in urine by As3±-Ce4± catalytic spectrophotometry （WS/T 107-2006）, iodine content in urine was detected. Rats were anesthetized intraperitoneally with 25% urethane, blood from abdominal aortic was collected to determinate the serum thyroid hormone [total triiodothyronine （TT3）, total thyroxine （TT4）, free triiodothyronine （TT3）, free thyroxine （FT4）] level in rats by automatic electrochemical luminescence immunoassay. All the rats were sacrificed to analyze the thyroid weight. Results ①The urine iodine showed significant differences in the four groups （X2 = 25.24, P 〈 0.05）. The median of urine iodine concentration in the LI, NI, KIO3 and DIT groups were 3.00, 286.14, 223.37, 214.33 μg/L, respectively. The urine iodine concentration in LI group was significantly lower than those of other three groups （all P 〈 0.05）. ② The serum TT3, TT4, FT3, FTg levels showed significant differences in the four groups （F = 63.48, 140.73, 130.20, 365.27, all P 〈 0.05）. And the hormone levels in KIO3 group were lower than those of the DIT group [TT3：（1.57 ± 0.20） vs. （1.97 ± 0.18） mmol/L, TT4：（51.23 ± 4.90） vs. （71.94 ± 5.27） mmol/L, FT4 （5.34 ± 0.45） vs. （6.98 ± 0.33） pmol/L, FT4：（26.18 ± 2.30） vs. （35.47 ± 2.28） pmol/L, all P 〈 0.05].③The color of thyroid in KIO3 and DIT groups became pale pink. The absolute and relative thyroid weight showed significant differences in the four groups （F = 225.05, 345.40, all P 〈 0.05）. The absolute thyroid weight [（31.76 ± 1.75） mg] and relative thyroid weight [（11.69± 3.47） mg/100g] in DIT group was lower than that of the KIO3 group [（36.31 ± 5.23） mg, （12.83 ± 4.38） mg/100 g, all P 〈 0.05]. Conclusion Animal experimental results show that DIT has a better iodine-supplementing efficacy than that of KIO3.
出处
《中华地方病学杂志》
CAS
CSCD
北大核心
2016年第3期170-173,共4页
Chinese Journal of Endemiology
基金
黑龙江省普通高等学校病因流行病学重点实验室开放课题资助项目（2012-14）
