title: Upregulation of mRNA myocardium calcium handling in rats submitted to exercise and food restriction.
abstract: BACKGROUND
  Chronic exercise and food restriction (FR) have directionally opposite changes in transcription of molecular structures of calcium handling and thyroid hormone (TH) status.
  
  
  OBJECTIVE
  Evaluate the association of chronic exercise and FR on serum thyroid hormones and gene transcription of molecular structures of intracellular calcium transients and thyroid receptors in myocardium of rats.
  
  
  METHODS
  Male Wistar Kyoto rats, divided into two groups: control (C, n = 7), FR (R50, n = 7), chronic exercise (EX, n = 7) and chronic exercise + FR (EX50, n = 7). FR was of 50% and exercise was swimming (1 hour/day, 5 days/week, during 12 weeks). Serum concentrations of T3, T4 and TSH were determined. The mRNA gene expression of the sarcoplasmatic reticulum calcium pump (SERCA2a), phospholamban (PLB), Na+/Ca+2 exchanger (NCX), calcium channel L-type (L-channel), ryanodine (RYR), calsequestrin (CQS) and HT receptor (TRα1 and TRβ1) of the myocardium was performed by PCR real-time.
  
  
  RESULTS
  FR reduced serum levels of T4 and TSH and TRα1 mRNA and increased the expression of PLB, NCX and L-channel. Exercise increased the TRβ1 receptor, L-channel and NCX. The association of exercise and FR reduced plasma T4 and TSH, TRβ1 mRNA increase, SERCA2a, NCX and PLB, and there was a significant correlation of TRβ1 with CQS and NXC.
  
  
  CONCLUSIONS
  Chronic exercise and food restriction increased the mRNA of transient Ca2+ proteins; however, TH-receptor axis cannot participate in the transcription of mRNA of myocardial calcium transient proteins.
authors.affiliation: Instituto de Ciências da Saúde, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil. mario@ufmt.br
authors.forename: Mário Mateus
authors.initials: MM
authors.lastname: Sugizaki
authors.forename: Ana Paula Lima
authors.initials: AP
authors.lastname: Leopoldo
authors.forename: Sandro José
authors.initials: SJ
authors.lastname: Conde
authors.forename: Dijon Salome
authors.initials: DS
authors.lastname: Campos
authors.forename: Ricardo
authors.initials: R
authors.lastname: Damato
authors.forename: André Soares
authors.initials: AS
authors.lastname: Leopoldo
authors.forename: André Ferreira do
authors.initials: AF
authors.lastname: Nascimento
authors.forename: Silvio de Assis
authors.initials: Sde A
authors.lastname: Oliveira Júnior
authors.forename: Antonio Carlos
authors.initials: AC
authors.lastname: Cicogna
mesh_terms: D000818:Animals; D020746:Calcium Channels, L-Type / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000378:metabolism; D031204:Caloric Restriction; D002155:Calsequestrin / Q000378:metabolism; D015870:Gene Expression; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D060888:Real-Time Polymerase Chain Reaction; D011988:Receptors, Thyroid Hormone / Q000378:metabolism; D012433:Ryanodine / Q000378:metabolism; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases / Q000378:metabolism; D019831:Sodium-Calcium Exchanger / Q000378:metabolism; D013963:Thyroid Hormones / Q000097:blood; D013997:Time Factors; D015854:Up-Regulation; D000099211:Phospholamban
chemical_list: D020746:Calcium Channels, L-Type; D002135:Calcium-Binding Proteins; D002155:Calsequestrin; D012333:RNA, Messenger; D011988:Receptors, Thyroid Hormone; D012433:Ryanodine; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D019831:Sodium-Calcium Exchanger; D013963:Thyroid Hormones; D000099211:Phospholamban