ASSAY OF TYPE I IODOTHYRONINE DEIODINASE ACTIVITY AND mRNA EXPRESSION IN THYROID IN RATS OF DIFFERENT IODINE NUTRITION STATUS
- VernacularTitle:不同碘营养对大鼠甲状腺Ⅰ型脱碘酶活性及mRNA水平的影响
- Author:
Kun WANG
;
Yina SUN
;
Jiayu LIU
;
Xueqin ZHAO
;
Yuqin YAN
;
Zupei CHEN
- Publication Type:Journal Article
- Keywords:
type I deiodinase;
thyroid function;
iodine deficiency;
iodine excess
- From:
Acta Nutrimenta Sinica
2004;0(05):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To further investigate the effects of iodine intake on thyroid function and its possible mechanism. Method: Wistar rats were randomly divided into six groups: LI, NI, 5HI, 10HI, 50HI, 100HI. Different groups of rats were fed with feed and water of different iodine content. 3, 6 and 12 months after administration, they were sacrificed and thyroids were excised. The thyroid D1 mRNA expression level was determined by RT-PCR semi-quantitative method and the thyroid D1 activity was analyzed by using 125I-rT3 as substrate. Results: Compared with NI group, the thyroid D1 mRNA expression was decreased in all HI groups, and D1 activity was significantly higher in LI group and lower in HI groups. There was a tendency of decrease in D1 activity with increased doses of iodine intakes. Conclusion: In the case of iodine deficiency, thyroid D1 activity will increase greatly in order to convert more T4 to T3, but deficient iodine intake doesn’t improve thyroid D1 mRNA expression. Excess iodine can inhibit both thyroid D1 mRNA expression and its activity.
