title: Moderate exercise training promotes adaptations in coronary blood flow and adenosine production in normotensive rats.
abstract: OBJECTIVE
  Aerobic exercise training prevents cardiovascular risks. Regular exercise promotes functional and structural adaptations that are associated with several cardiovascular benefits. The aim of this study is to investigate the effects of swimming training on coronary blood flow, adenosine production and cardiac capillaries in normotensive rats.
  
  
  METHODS
  Wistar rats were randomly divided into two groups: control (C) and trained (T). An exercise protocol was performed for 10 weeks and 60 min/day with a tail overload of 5% bodyweight. Coronary blood flow was quantified with a color microsphere technique, and cardiac capillaries were quantified using light microscopy. Adenine nucleotide hydrolysis was evaluated by enzymatic activity, and protein expression was evaluated by western blot. The results are presented as the means ± SEMs (p<0.05).
  
  
  RESULTS
  Exercise training increased the coronary blood flow and the myocardial capillary-to-fiber ratio. Moreover, the circulating and cardiac extracellular adenine nucleotide hydrolysis was higher in the trained rats than in the sedentary rats due to the increased activity and protein expression of enzymes, such as E-NTPDase and 59'-nucleotidase.
  
  
  CONCLUSIONS
  Swimming training increases coronary blood flow, number of cardiac capillaries, and adenine nucleotide hydrolysis. Increased adenosine production may be an important contributor to the enhanced coronary blood flow and angiogenesis that were observed in the exercise-trained rats; collectively, these results suggest improved myocardial perfusion.
authors.affiliation: University of São Paulo, School of Physical Education and Sports, Laboratory of Biochemistry, São Paulo/SP, Brazil. feroberta@usp.br
authors.forename: Fernanda R
authors.initials: FR
authors.lastname: Roque
authors.forename: Ursula Paula Renó
authors.initials: UP
authors.lastname: Soci
authors.forename: Katia
authors.initials: K
authors.lastname: De Angelis
authors.forename: Marcele A
authors.initials: MA
authors.lastname: Coelho
authors.forename: Cristina R
authors.initials: CR
authors.lastname: Furstenau
authors.forename: Dalton V
authors.initials: DV
authors.lastname: Vassallo
authors.forename: Maria Claudia
authors.initials: MC
authors.lastname: Irigoyen
authors.forename: Edilamar M
authors.initials: EM
authors.lastname: Oliveira
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000241:Adenosine / Q000096:biosynthesis*; D000818:Animals; D001794:Blood Pressure / Q000502:physiology*; D002196:Capillaries / Q000201:enzymology / Q000502:physiology*; D003326:Coronary Circulation / Q000502:physiology*; D005110:Extracellular Space / Q000201:enzymology; D008297:Male; D010805:Physical Conditioning, Animal / Q000502:physiology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013550:Swimming / Q000502:physiology
chemical_list: D000241:Adenosine