title: Effect of ascorbic acid on long-term cold exposure induced changes in thyroid activity in Sprague Dawley rats.
abstract: OBJECTIVE
  To determine the effect of ascorbic acid supplementation on long-term cold exposure induced changes in thyroid activity in Sprague-Dawley rats.
  
  
  METHODS
  Experimental study.
  
  
  METHODS
  Physiology Department of Islamic International Medical College, Rawalpindi, National Institute of Health, Islamabad and Railway Hospital, Rawalpindi, from January to December 2009.
  
  
  METHODS
  Ninety Sprague-Dawley rats were randomly divided into three groups of control, cold exposed and cold exposed along with ascorbic acid supplementation. After one month, their thyroid levels were analyzed by using chemiluminescent immunometric assay on Siemens Immulite 2000 Analyzer.
  
  
  RESULTS
  After 4 weeks of cold exposure to experimental animals, the thyroid activity was raised significantly in the cold exposed group as compared to the control group (p-value for T3 difference = 0.004, T4 difference = 0.002 and TSH difference < 0.001). Supplementation with ascorbic acid in the third group normalized the thyroid hormone activity with p-value for difference in levels of T3 being 0.6661, T4 = 0.027 and TSH = 0.0028.
  
  
  CONCLUSIONS
  Ascorbic acid prevented the cold induced changes in thyroid hormone levels in rodents.
authors.affiliation: Department of Physiology, Islamic International Medical College, Rawalpindi.
authors.forename: Aneeqa
authors.initials: A
authors.lastname: Rashid
authors.forename: Umar Ali
authors.initials: UA
authors.lastname: Khan
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology*; D003080:Cold Temperature; D008163:Luminescent Measurements; D008297:Male; D009929:Organ Size; D051381:Rats; D017207:Rats, Sprague-Dawley; D013961:Thyroid Gland / Q000187:drug effects*; D013963:Thyroid Hormones / Q000097:blood; D013997:Time Factors
chemical_list: D000975:Antioxidants; D013963:Thyroid Hormones; D001205:Ascorbic Acid