title: Bezold-Jarisch reflex in sino-aortic denervated malnourished rats.
abstract: In this study we assessed the role of Bezold-Jarisch reflex (BJR) in the regulation of blood pressure (BP) of malnourished (MN) and control rats (CN) with sino-aortic denervation (SAD). Fischer rats were fed diets containing either 6% (MN) or 15% (CN) protein for 35 days after weaning. These rats underwent sham or SAD and catheterization of femoral artery and vein for BP measurements and drug injection. Phenylbiguanide (PBG 5 μg/kg, i.v.) for activation BJR, produced bradycardia (-317±22 bpm for CN vs. -372±16 bpm for MN) and hypotension (-57±4 mm Hg for CN vs. -54±6 mm Hg for MN. After SAD, MN rats had reduced hypotensive (-37±7 mm Hg for MN vs. -82±6 mm Hg for CN) and bradycardic (-124±17 for MN vs. -414±20 bpm CN) responses to BJR activation. To evaluate the contribution of the parasympathetic component due to BJR for the fall in BP, methyl atropine bromide, was given between two injections of PBG (5 μg/kg) separated by 10 min each other. Both bradycardic (-216±21 bpm before and -4±3 bpm after for CN -226±43 bpm before and -9±20 bpm after for MN) and hypotensive (-42±4 mm Hg before and -6±1 mm Hg after for CN -33±9 mm Hg before and -5±2 mm Hg after for MN) responses were abolished in CN and MN groups. These data indicate that dietary protein malnutrition changes the relation between baroreflex and BJR required for maintenance of the BP during malnourishment.
authors.affiliation: Federal University of Bahia (UFBA), Campus Vitória da Conquista, BA, Brazil.
authors.forename: Vanessa Moraes
authors.initials: VM
authors.lastname: Bezerra
authors.forename: Carlos Henrique
authors.initials: CH
authors.lastname: Xavier
authors.forename: Rodrigo Cunha Alvim
authors.initials: RC
authors.lastname: de Menezes
authors.forename: Marco Antônio Peliky
authors.initials: MA
authors.lastname: Fontes
authors.forename: Leonardo Máximo
authors.initials: LM
authors.lastname: Cardoso
authors.forename: Luciano Gonçalves
authors.initials: LG
authors.lastname: Fernandes
authors.forename: Deoclécio Alves
authors.initials: DA
authors.lastname: Chianca
mesh_terms: D000818:Animals; D001286:Atropine Derivatives / Q000494:pharmacology; D001645:Biguanides / Q000494:pharmacology; D001794:Blood Pressure / Q000502:physiology*; D001835:Body Weight / Q000502:physiology; D003714:Denervation; D004305:Dose-Response Relationship, Drug; D006339:Heart Rate / Q000502:physiology; D008297:Male; D044342:Malnutrition / Q000503:physiopathology*; D018727:Muscarinic Antagonists / Q000494:pharmacology; D009599:Nitroprusside / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D011502:Protein-Energy Malnutrition / Q000503:physiopathology; D051381:Rats; D011916:Rats, Inbred F344; D012018:Reflex / Q000502:physiology*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D012849:Sinoatrial Node / Q000502:physiology*; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D001286:Atropine Derivatives; D001645:Biguanides; D018727:Muscarinic Antagonists; D017366:Serotonin Receptor Agonists; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D009599:Nitroprusside; D010656:Phenylephrine; C006649:methylatropine; C008846:phenyl biguanide