title: Cardiac and pulmonary arterial remodeling after sinoaortic denervation in normotensive rats.
abstract: Blood pressure variability (BPV) and baroreflex dysfunction may contribute to end-organ damage process. We investigated the effects of baroreceptor deficit (10 weeks after sinoaortic denervation - SAD) on hemodynamic alterations, cardiac and pulmonary remodeling. Cardiac function and morphology of male Wistar intact rats (C) and SAD rats (SAD) (n=8/group) were assessed by echocardiography and collagen quantification. BP was directly recorded. Ventricular hypertrophy was quantified by the ratio of left ventricular weight (LVW) and right ventricular weight (RVW) to body weight (BW). BPV was quantified in the time and frequency domains. The atrial natriuretic peptide (ANP), alpha-skeletal actin (α-skelectal), collagen type I and type III genes mRNA expression were evaluated by RT-PCR. SAD did not change BP, but increased BPV (11±0.49 vs. 5±0.3 mmHg). As expected, baroreflex was reduced in SAD. Pulmonary artery acceleration time was reduced in SAD. In addition, SAD impaired diastolic function in both LV (6.8±0.26 vs. 5.02±0.21 mmHg) and RV (5.1±0.21 vs. 4.2±0.12 mmHg). SAD increased LVW/BW in 9% and RVW/BW in 20%, and augmented total collagen (3.8-fold in LV, 2.7-fold in RV, and 3.35-fold in pulmonary artery). Also, SAD increased type I (~6-fold) and III (~5-fold) collagen gene expression. Denervation increased ANP expression in LV (75%), in RV (74%) and increased α-skelectal expression in LV (300%) and in RV (546%). Baroreflex function impairment by SAD, despite not changing BP, induced important adjustments in cardiac structure and pulmonary hypertension. These changes may indicate that isolated baroreflex dysfunction can modulate target tissue damage.
authors.affiliation: Experimental Hypertension Laboratory, Hypertension Unit, Heart Institute, Department of Pathology, University of Sao Paulo Medical School, São Paulo, SP, Brazil.
authors.forename: K
authors.initials: K
authors.lastname: Flues
authors.forename: I C
authors.initials: IC
authors.lastname: Moraes-Silva
authors.forename: C
authors.initials: C
authors.lastname: Mostarda
authors.forename: P R M
authors.initials: PR
authors.lastname: Souza
authors.forename: G P
authors.initials: GP
authors.lastname: Diniz
authors.forename: E D
authors.initials: ED
authors.lastname: Moreira
authors.forename: A C
authors.initials: AC
authors.lastname: Piratello
authors.forename: M L Barreto
authors.initials: ML
authors.lastname: Chaves
authors.forename: K
authors.initials: K
authors.lastname: De Angelis
authors.forename: Vera Maria Cury
authors.initials: VM
authors.lastname: Salemi
authors.forename: M C
authors.initials: MC
authors.lastname: Irigoyen
authors.forename: E G
authors.initials: EG
authors.lastname: Caldini
mesh_terms: D000818:Animals; D017763:Autonomic Denervation / Q000009:adverse effects / Q000379:methods; D017704:Baroreflex / Q000502:physiology*; D004195:Disease Models, Animal; D065627:Familial Primary Pulmonary Hypertension; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D006976:Hypertension, Pulmonary / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*; D017379:Hypertrophy, Left Ventricular / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D011311:Pressoreceptors / Q000293:injuries / Q000503:physiopathology* / Q000601:surgery; D011651:Pulmonary Artery / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D051381:Rats; D017208:Rats, Wistar; D014463:Ultrasonography