title: Central N-acetylcysteine effects on baroreflex in juvenile spontaneously hypertensive rats.
abstract: In this study, we evaluated the acute effects of central NAC administration on baroreflex in juvenile SHR and Wistar Kyoto (WKY) rats. Male SHR and WKY rats (8-10 weeks old) were implanted with a stainless steel guide cannula into the fourth cerebral ventricle (4th V). The femoral artery and vein were cannulated for mean arterial pressure (MAP) and heart rate (HR) measurement and drug infusion, respectively. After basal MAP and HR recordings, the baroreflex was tested with a pressor dose of phenylephrine (PHE, 8 μg/kg, bolus) and a depressor dose of sodium nitroprusside (SNP, 50 μg/kg, bolus). Baroreflex was evaluated before, 5, 15, 30 and 60 minutes after NAC injection into the 4th V. Vehicle treatment did not change baroreflex responses in WKY and SHR. Central NAC slightly but significantly increased basal HR at 15 minutes and significantly reduced PHE-induced increase in MAP 30 and 60 minutes after NAC injection (p < 0.05) in WKY rats. In relation to SHR, NAC decreased HR range 15 and 30 minutes after its administration. In conclusion, acute NAC into the 4th V does not improve baroreflex in juvenile SHR.
authors.affiliation: Departamento de Medicina, Disciplina de Cardiologia, Universidade Federal de São Paulo (UNIFESP), Brazil. vitor.valenti@gmail.com
authors.forename: Vitor E
authors.initials: VE
authors.lastname: Valenti
authors.forename: Luiz Carlos
authors.initials: LC
authors.lastname: De Abreu
authors.forename: Monica A
authors.initials: MA
authors.lastname: Sato
authors.forename: Paulo H N
authors.initials: PH
authors.lastname: Saldiva
authors.forename: Fernando L A
authors.initials: FL
authors.lastname: Fonseca
authors.forename: Gisele
authors.initials: G
authors.lastname: Giannocco
authors.forename: Andreas R P
authors.initials: AR
authors.lastname: Riera
authors.forename: Celso
authors.initials: C
authors.lastname: Ferreira
mesh_terms: D000111:Acetylcysteine / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D017704:Baroreflex / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D002408:Catheters, Indwelling; D016166:Free Radical Scavengers / Q000494:pharmacology*; D007276:Injections, Intraventricular; D008297:Male; D009599:Nitroprusside / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D016166:Free Radical Scavengers; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D009599:Nitroprusside; D010656:Phenylephrine; D000111:Acetylcysteine