title: Hypertrophic response of the association of thyroid hormone and exercise in the heart of rats.
abstract: BACKGROUND
  Cardiac hypertrophy is a component of cardiac remodeling occurring in response to an increase of the activity or functional overload of the heart.
  
  
  OBJECTIVE
  Assess hypertrophic response of the association of thyroid hormone and exercise in the rat heart.
  
  
  METHODS
  We used 37 Wistar rats, male, adults were randomly divided into four groups: control, hormone (TH), exercise (E), thyroid hormone and exercise (H+E); the group received daily hormone levothyroxine sodium by gavage at a dose of 20 μg thyroid hormone/100g body weight, the exercise group took swimming five times a week, with additional weight corresponding to 20% of body weight for six weeks; in group H+E were applied simultaneously TH treatment groups and E. The statistics used was analysis of variance, where appropriate, by Tukey test and Pearson correlation test.
  
  
  RESULTS
  The T4 was greater in groups TH and H+E. The total weight of the heart was greater in patients who received thyroid hormone and left ventricular weight was greater in the TH group. The transverse diameter of cardiomyocytes increased in groups TH, E and H+E. The percentage of collagen was greater in groups E and H+E Correlation analysis between variables showed distinct responses.
  
  
  CONCLUSIONS
  The association of thyroid hormone with high-intensity exercise produced cardiac hypertrophy, and generated a standard hypertrophy not directly correlated to the degree of fibrosis.
authors.forename: Fernanda Rodrigues de
authors.initials: FR
authors.lastname: Souza
authors.forename: Elmiro Santos
authors.initials: ES
authors.lastname: Resende
authors.forename: Leandro
authors.initials: L
authors.lastname: Lopes
authors.forename: Alexandre
authors.initials: A
authors.lastname: Gonçalves
authors.forename: Rafaella
authors.initials: R
authors.lastname: Chagas
authors.forename: Thiago
authors.initials: T
authors.lastname: Fidale
authors.forename: Poliana
authors.initials: P
authors.lastname: Rodrigues
mesh_terms: D000818:Animals; D001835:Body Weight; D059267:Cardiomegaly, Exercise-Induced / Q000187:drug effects* / Q000502:physiology*; D006321:Heart / Q000187:drug effects* / Q000502:physiology*; D008297:Male; D023421:Models, Animal; D009929:Organ Size; D010805:Physical Conditioning, Animal; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values; D013974:Thyroxine / Q000008:administration & dosage*; D013997:Time Factors; D020257:Ventricular Remodeling / Q000187:drug effects / Q000502:physiology
chemical_list: D013974:Thyroxine