title: ATZ (3-amino-1,2,4-triazole) injected into the fourth cerebral ventricle influences the Bezold-Jarisch reflex in conscious rats.
abstract: OBJECTIVE
  Many studies have investigated the importance of oxidative stress on the cardiovascular system. In this study we evaluated the effects of central catalase inhibition on cardiopulmonary reflex in conscious Wistar rats.
  
  
  METHODS
  Male Wistar rats were implanted with a stainless steel guide cannula in the fourth cerebral ventricle. The femoral artery and vein were cannulated for mean arterial pressure and heart rate measurement and for drug infusion, respectively. After basal mean arterial pressure and heart rate recordings, the cardiopulmonary reflex was tested with a dose of phenylbiguanide (PBG, 8 μg/kg, bolus). Cardiopulmonary reflex was evaluated before and μ l15 minutes after 1.0 μl 3-amino-1,2,4-triazole (ATZ, 0.01 g/100 μl)0.01 g/100 μl) injection into the fourth cerebral ventricle. Vehicle treatment did not change cardiopulmonary reflex responses.
  
  
  RESULTS
  Central ATZ significantly increased hypotensive responses without influencing the bradycardic reflex.
  
  
  CONCLUSIONS
  ATZ injected into the fourth cerebral ventricle increases sympathetic inhibition but does not change the parasympathetic component of the cardiopulmonary reflex in conscious Wistar rats.
authors.affiliation: Departamento de Medicina, Disciplina de Cardiologia, Universidade Federal de São Paulo, São Paulo, São Paulo, Brazil. valenti@unifesp.br
authors.forename: Vitor E
authors.initials: VE
authors.lastname: Valenti
authors.forename: Luiz Carlos de
authors.initials: LC
authors.lastname: Abreu
authors.forename: Monica A
authors.initials: MA
authors.lastname: Sato
authors.forename: Celso
authors.initials: C
authors.lastname: Ferreira
mesh_terms: D000640:Amitrole / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D017704:Baroreflex / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D003243:Consciousness / Q000187:drug effects*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D020546:Fourth Ventricle / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D007276:Injections, Intraventricular; D008297:Male; D023421:Models, Animal; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar
chemical_list: D004791:Enzyme Inhibitors; D000640:Amitrole