title: Different Doses and Routes of Administration of Methimazole Affect Thyroid Status in Methimazole-induced Hypothyroidism in Rats.
abstract: OBJECTIVE
  It is agreed that methimazole (MMI) can be administered to induce hypothyroidism. However, there are conflicting data about its effect on thyroid function and development in rats through different administrations. In the present study, we established and compared differences of the rat hypothyroid model induced by MMI added to drinking water or given through an intragastric tube.
  
  
  METHODS
  Sixty-four male Wistar rats were randomly divided into seven groups. Methimazole was added to the drinking water (0.025%, 0.04% or 0.1% wt/vol), or through intragastric gavage (5 mg/100 g body weight (bw) or 8 mg/100 g bw) one time each day for 21 days. The rats were weighed every seven days. Blood samples were taken in order to detect the concentrations of serum triiodothyronine (T3), thyroxine (T4) and thyrotropin (TSH) at the end of the experiments.
  
  
  RESULTS
  Our results indicate that the effect of methimazole on a rat's thyroid function and body weight is similar in both the group given 0.1% concentration in drinking water and the group which received 8 mg/100 g bw once daily through the intragastric tube. Also, a similar effect was observed in the 0.025%, 0.04% and 5 mg/100 g bw groups.
  
  
  CONCLUSIONS
  These findings suggest that a relationship between the concentration of MMI by oral administration and the dose of it through intragastric administration could exist, and may contribute to inducing hypothyroidism in rats.
authors.affiliation: Department of Endocrinology, Shandong Provincial Hospital affiliated to Shandong University, Ji'nan 250021, China. E-mail: zhaoxinli0301@143.com.|Shandong Clinical Medical Center of Endocrinology and Metabolism, Ji'nan 250021, China.|Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji'nan 250021, China. E-mail: zhaoxinli0301@143.com.
authors.forename: X-L
authors.initials: XL
authors.lastname: Zhou
authors.affiliation: Department of Endocrinology, Shandong Provincial Hospital affiliated to Shandong University, Ji'nan 250021, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Han
authors.affiliation: Department of Family Practice, University of British Columbia, BC, Canada.
authors.forename: W J
authors.initials: WJ
authors.lastname: Mail
authors.affiliation: Department of Endocrinology, Shandong Provincial Hospital affiliated to Shandong University, Ji'nan 250021, China.|Shandong Clinical Medical Center of Endocrinology and Metabolism, Ji'nan 250021, China.|Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji'nan 250021, China.
authors.forename: J
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Endocrinology, Shandong Provincial Hospital affiliated to Shandong University, Ji'nan 250021, China.|Shandong Clinical Medical Center of Endocrinology and Metabolism, Ji'nan 250021, China.|Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji'nan 250021, China.
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Endocrinology, Shandong Provincial Hospital affiliated to Shandong University, Ji'nan 250021, China.|Shandong Clinical Medical Center of Endocrinology and Metabolism, Ji'nan 250021, China.|Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji'nan 250021, China.
authors.forename: L
authors.initials: L
authors.lastname: Feng
authors.affiliation: Shandong Clinical Medical Center of Endocrinology and Metabolism, Ji'nan 250021, China.|Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji'nan 250021, China.|Central Laboratory, Shandong Provincial Hospital affiliated to Shandong University, Ji'nan 250021, China.
authors.forename: L
authors.initials: L
authors.lastname: Gao
authors.affiliation: Department of Endocrinology, Shandong Provincial Hospital affiliated to Shandong University, Ji'nan 250021, China. E-mail: jiajunzhaocn@163.com.|Shandong Clinical Medical Center of Endocrinology and Metabolism, Ji'nan 250021, China.|Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Ji'nan 250021, China. jiajunzhaocn@163.com.
authors.forename: J-J
authors.initials: JJ
authors.lastname: Zhao
keywords: Administration; hypothyroidism; methimazole; rat model; thyroid