MARIA CLAUDIA COSTA IRIGOYEN

(Fonte: Lattes)
Índice h a partir de 2011
30
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/59 - Laboratório de Biologia Celular, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/05 - Laboratório de Poluição Atmosférica Experimental, Hospital das Clínicas, Faculdade de Medicina
LIM/65, Hospital das Clínicas, Faculdade de Medicina

Resultados de Busca

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  • article 2 Citação(ões) na Scopus
    Effects of sympathectomy on myocardium remodeling and function
    (2021) JORDAO, Mauricio Rodrigues; PESSOA, Fernanda G.; FONSECA, Keila C. B.; ZANONI, Fernando; SALEMI, Vera M. C.; SOUZA, Leandro E.; RIBEIRO, Orlando N.; FERNANDES, Fabio; IRIGOYEN, Maria Claudia; MOREIRA, Luiz Felipe P.; MADY, Charles; RAMIRES, Felix Jose Alvarez
    OBJECTIVES: To evaluate the effects of sympathectomy on the myocardium in an experimental model. METHODS: The study evaluated three groups of male Wistar rats: control (CT; n=15), left unilateral sympathectomy (UNI; n=15), and bilateral sympathectomy (BIL; n=31). Sympathectomy was performed by injection of absolute alcohol into the space of the spinous process of the C7 vertebra. After 6 weeks, we assessed the chronotropic properties at rest and stress, cardiovascular autonomic modulation, myocardial and peripheral catecholamines, and beta-adrenergic receptors in the myocardium. The treadmill test consisted of an escalated protocol with a velocity increment until the maximal velocity tolerated by the animal was reached. RESULTS: The bilateral group had higher levels of peripheral catecholamines, and consequently, a higher heart rate (HR) and blood pressure levels. This suggests that the activation of a compensatory pathway in this group may have deleterious effects. The BIL group had basal tachycardia immediately before the exercise test and increased tachycardia at peak exercise (p<0.01); the blood pressure had the same pattern (p=0.0365). The variables related to autonomic modulation were not significantly different between groups, with the exception of the high frequency (HF) variable, which showed significant differences in CT vs UNI. There was no significant difference in beta receptor expression between groups. There was a higher concentration of peripheral norepinephrine in the BIL group (p=0.0001), and no significant difference in myocardial norepinephrine (p=0.09). CONCLUSION: These findings suggest that an extra cardiac compensatory pathway increases the sympathetic tonus and maintains a higher HR and higher levels of peripheral catecholamines in the procedure groups. The increase in HF activity can be interpreted as an attempt to increase the parasympathetic tonus to balance the greater sympathetic activity.
  • article 27 Citação(ões) na Scopus
    Exercise training prevents diastolic dysfunction induced by metabolic syndrome in rats
    (2012) MOSTARDA, Cristiano; MORAES-SILVA, Ivana Cinthya; SALEMI, Vera Maria Cury; MACHI, Jacqueline Freire; RODRIGUES, Bruno; ANGELIS, Katia De; FARAH, Vera de Moura Azevedo; IRIGOYEN, Maria Claudia
    OBJECTIVE: High fructose consumption contributes to the incidence of metabolic syndrome and, consequently, to cardiovascular outcomes. We investigated whether exercise training prevents high fructose diet-induced metabolic and cardiac morphofunctional alterations. METHODS: Wistar rats receiving fructose overload (F) in drinking water (100 g/l) were concomitantly trained on a treadmill (FT) for 10 weeks or kept sedentary. These rats were compared with a control group (C). Obesity was evaluated by the Lee index, and glycemia and insulin tolerance tests constituted the metabolic evaluation. Blood pressure was measured directly (Windaq, 2 kHz), and echocardiography was performed to determine left ventricular morphology and function. Statistical significance was determined by one-way ANOVA, with significance set at p<0.05. RESULTS: Fructose overload induced a metabolic syndrome state, as confirmed by insulin resistance (F: 3.6 +/- 0.2 vs. C: 4.5 +/- 0.2 mg/dl/min), hypertension (mean blood pressure, F: 118 +/- 3 vs. C: 104 +/- 4 mmHg) and obesity (F: 0.31 +/- 0.001 vs. C: 0.29 +/- 0.001 g/mm). Interestingly, fructose overload rats also exhibited diastolic dysfunction. Exercise training performed during the period of high fructose intake eliminated all of these derangements. The improvements in metabolic parameters were correlated with the maintenance of diastolic function. CONCLUSION: The role of exercise training in the prevention of metabolic and hemodynamic parameter alterations is of great importance in decreasing the cardiac morbidity and mortality related to metabolic syndrome.