title: Resistance training controls arterial blood pressure in rats with L-NAME- induced hypertension.
abstract: BACKGROUND
  Arterial hypertension is a multifactorial chronic condition caused by either congenital or acquired factors.
  
  
  OBJECTIVE
  To evaluate the effects of Resistance Training (RT) on arterial pressure, and on vascular reactivity and morphology, of L-NAME-treated hypertensive rats.
  
  
  METHODS
  Male Wistar rats (200 - 250 g) were allocated into Sedentary Normotensive (SN), Sedentary Hypertensive (SH) and Trained Hypertensive (TH) groups. Hypertension was induced by adding L-NAME (40 mg/Kg) to the drinking water for four weeks. Arterial pressure was evaluated before and after RT. RT was performed using 50% of 1RM, 3 sets of 10 repetitions, 3 times per week for four weeks. Vascular reactivity was measured in rat mesenteric artery rings by concentration-response curves to sodium nitroprusside (SNP); phenylephrine (PHE) was also used for histological and stereological analysis.
  
  
  RESULTS
  Resistance training inhibited the increase in mean and diastolic arterial pressures. Significant reduction was observed in Rmax (maximal response) and pD2 (potency) of PHE between SH and TH groups. Arteries demonstrated normal intima, media and adventitia layers in all groups. Stereological analysis demonstrated no significant difference in luminal, tunica media, and total areas of arteries in the SH and TH groups when compared to the SN group. Wall-to-lumen ratio of SH arteries was significantly different compared to SN arteries (p<0.05) but there was no difference when compared to TH arteries.
  
  
  CONCLUSIONS
  RT was able to prevent an increase in blood pressure under the conditions in this study. This appears to involve a vasoconstrictor regulation mechanism and maintenance of luminal diameter in L-NAME induced hypertensive rats.
authors.affiliation: Departamento de Fisiologia, Universidade Federal de Sergipe, São Cristovão, Sergipe, Brasil.
authors.forename: Ayslan Jorge Santos de
authors.initials: AJ
authors.lastname: Araujo
authors.forename: Anne Carolline Veríssimo dos
authors.initials: AC
authors.lastname: Santos
authors.forename: Karine dos Santos
authors.initials: Kdos S
authors.lastname: Souza
authors.forename: Marlúcia Bastos
authors.initials: MB
authors.lastname: Aires
authors.forename: Valter Joviniano
authors.initials: VJ
authors.lastname: Santana-Filho
authors.forename: Emerson Ticona
authors.initials: ET
authors.lastname: Fioretto
authors.forename: Marcelo Mendonça
authors.initials: MM
authors.lastname: Mota
authors.forename: Márcio Roberto Viana
authors.initials: MR
authors.lastname: Santos
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology*; D004195:Disease Models, Animal; D006973:Hypertension / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D008297:Male; D017538:Mesenteric Artery, Superior / Q000502:physiology; D019331:NG-Nitroarginine Methyl Ester; D009599:Nitroprusside / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D010805:Physical Conditioning, Animal / Q000379:methods*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D055070:Resistance Training; D014661:Vasoconstriction / Q000502:physiology*; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D009599:Nitroprusside; D010656:Phenylephrine; D019331:NG-Nitroarginine Methyl Ester