title: Cimetidine administration decreases radiogenic damage on the thyroid gland in mice.
abstract: OBJECTIVE
  To study if Cimetidine administration could ameliorate the thyroid damage in external radiation.
  
  
  METHODS
  Forty healthy male adult mice were used in the present study. The animals were randomized into four groups. Untreated mice (Group 1) that received 1 mg/kg saline intraperitoneally (IP). Group 2 received a single 10 Gy gamma radiation dose with 1 mg/kg saline IP and group 3 were treated with Cimetidine IP. Group 4 was irradiated 1 hour after treatment with Cimetidine. The serum were assayed for the contents of triiodothyronine (T3), tetraiodothyronine (T4), thyroid stimulating hormone (TSH), Free T4 (FT4) and Cortisol using a radioimmunological technique 7 days following radiation. The thyroid tissue was processed and stained with hematoxylin and eosin (H&E), and periodic acid-Schiff (PAS) for histological examination. Data were statistically analyzed using Tukey's post-hoc test and were considered significant at p < 0.05.
  
  
  RESULTS
  External radiation resulted in weight loss and reduction of serum thyroid hormone levels. However, Cimetidine administration prevented marked changes. Histological study showed that Cimetidine injection to irradiated mice minimized the thyroid damage.
  
  
  CONCLUSIONS
  These findings suggested that Cimetidine administration 1 hour before radiation exposure was potent in ameliorating the thyroid damages.
authors.affiliation: Department of Anatomy, Islamic Azad University Tehran Medical Branch , Tehran , Iran.
authors.forename: Simin
authors.initials: S
authors.lastname: Fazelipour
authors.forename: Seyyed B
authors.initials: SB
authors.lastname: Kiaei
authors.forename: Zahra
authors.initials: Z
authors.lastname: Tootian
authors.forename: Seyyed A
authors.initials: SA
authors.lastname: Haeri
authors.forename: Omid
authors.initials: O
authors.lastname: Zehtabvar
authors.forename: Javad
authors.initials: J
authors.lastname: Sadeghinezhad
mesh_terms: D000818:Animals; D002927:Cimetidine / Q000008:administration & dosage*; D004334:Drug Administration Schedule; D005720:Gamma Rays / Q000009:adverse effects; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D011837:Radiation-Protective Agents / Q000008:administration & dosage*; D013961:Thyroid Gland / Q000187:drug effects* / Q000473:pathology / Q000528:radiation effects*; D013963:Thyroid Hormones / Q000097:blood
chemical_list: D011837:Radiation-Protective Agents; D013963:Thyroid Hormones; D002927:Cimetidine; D006854:Hydrocortisone
keywords: Cimetidine; external radiation; mouse; thyroid gland