title: [Effects of various iodin-nutritional on activity of T4 5'-and 5-deiodinase in rat brain].
abstract: OBJECTIVE
  To investigate the changing of T4 5'-and 5-deiodinase within rat brain under various iodin-nutritional states.
  
  
  METHODS
  Animal model of iodine-deficiency rat was performed and the rats were divided into 4 groups by the intake of iodine-nutrition, and then killed at an age of 20 days. The thyroid hormones level in serum was measured by ELISA and the activity of T(4) 5'-and 5-deiodinase within brain was analyzed.
  
  
  RESULTS
  In less-iodine (LI) group,TT4 and FT4 were accounting for 3.5% of the neutral-iodine (NI) group's, and FT3 was 174.0% of NI group's (P < 0.05). In NI group,TT4 and FT4 were 114.5% and 127.7% of NI group's (P < 0.05). In high-iodine (HI) group, TT4 and FT4 were 61.86% and 62.0% of NI group's, and FT3 was 184.9% of NI group's (P < 0.05). In LI group, the activity of T4 5'-deiodinase tissue of per gram (1.95 +/- 0.32) ngT3.microgT4(-1).h was significantly higher than that of NI group (P < 0.05), and the activity of 5-deiodinase (1.38 +/- 0.21) ngrT3.microg T4(-1).h(-1) is significantly less than that of NI group (1.59 +/- 0.23) (P < 0.05). In HI group the activity of T4 5'-and 5-deiodinase tissue of per gram (1.12 +/- 0.19 and 1.73 +/- 0.36) ngrT3.microgT4(-1).h(-1)was significantly less than that of NI group (P < 0.05).
  
  
  CONCLUSIONS
  The activity of T4 5'-deiodinase in iodine deficiency heightens and that in iodine excess is debased, the activity of T4 5-deiodinase in iodine deficiency and in iodine excess is debased.
authors.affiliation: Institute of Endocrinology, Tianjin Medical University, Tianjin 300070, China.
authors.forename: Shan-yi
authors.initials: SY
authors.lastname: Guo
authors.forename: Ai-jun
authors.initials: AJ
authors.lastname: Zuo
authors.forename: Nian-qing
authors.initials: NQ
authors.lastname: Liu
authors.forename: Xue-qin
authors.initials: XQ
authors.lastname: Zhao
authors.forename: Ruo-lin
authors.initials: RL
authors.lastname: Guo
authors.forename: Fang
authors.initials: F
authors.lastname: Zhang
authors.forename: Jing-yu
authors.initials: JY
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology*; D005260:Female; D007453:Iodide Peroxidase / Q000378:metabolism*; D007455:Iodine / Q000008:administration & dosage* / Q000172:deficiency*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D014284:Triiodothyronine; D007455:Iodine; D007453:Iodide Peroxidase; D013974:Thyroxine