Effect of Chronic Iodine Excess on Type Ⅱ Deiodinase in Hypothalamus and Serum Thyrotropin Releasing Hormone Level in Rats
10.12007/j.issn.0258-4646.2019.02.001
- VernacularTitle:慢性碘过量对大鼠下丘脑Ⅱ型脱碘酶及血清促甲状腺激素释放激素水平的影响
- Author:
Xin DU
1
;
Yaqiu JIANG
;
Ying SUN
Author Information
1. 中国医科大学附属第一医院内分泌科
- Keywords:
iodine excess;
thyrotropin releasing hormone;
type 2 deiodinase
- From:
Journal of China Medical University
2019;48(2):97-100
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect of chronic iodine excess on hypothalamic type Ⅱ deiodinase (D2) and serum thyrotropin releasing hormone (TRH) levels in rats. Methods One hundred and eighty four-week-old Wistar rats were randomly divided into control group (NI) and 3-fold, 6-fold, 10-fold, and 50-fold high iodine (HI) groups. Double distilled water and iodine solutions at concentrations of 277, 692, 1 245, and 6 788 μg/L were administered for 4, 8, 12, and 24 weeks, respectively. Brain tissue was taken after sacrifice, serum TRH levels were detected by ELISA, and hypothalamic D2 levels were detected by immunohistochemistry. Results Serum TRH levels in the 10-fold and 50-fold HI groups at 4 weeks, 6-fold and 50-fold HI groups at 8 weeks, 6-fold HI group at 12 weeks, and the 3-fold and 50-fold HI groups at 24 weeks were significantly lower than those in the control group (P ＜ 0.05). The results of immunohistochemistry revealed that the expression of hypothalamic D2 at each time-point was increased in the HI groups in comparison with the control group. Conclusion Chronic iodine excess can boost the expression of hypothalamic D2 and lessen the serum TRH level in rats.
