Evaluation of Cardiovascular Risk Factors in the Wistar Audiogenic Rat (WAR) Strain

Autor(es)

Fazan, Jr., Rubens ^[1] ; Silva, Carlos Alberto A. ^[1] ; Cortes Oliveira, Jose Antonio ^[1] ; Salgado, Helio Cesar ^[1] ; Montano, Nicola ^[2] ; Garcia-Cairasco, Norberto ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sch Med Ribeirao Preto, Dept Physiol, BR-14049 Ribeirao Preto, SP - Brazil

^[2] Univ Milan, Dept Clin Sci Luigi Sacco, Milan - Italy

• Tipo de documento: Artigo Científico
• Fonte: PLoS One; v. 10, n. 6 JUN 1 2015.
• Citações Web of Science: 8

Resumo

Introduction Risk factors for life-threatening cardiovascular events were evaluated in an experimental model of epilepsy, the Wistar Audiogenic Rat (WAR) strain. Methods We used long-term ECG recordings in conscious, one year old, WAR and Wistar control counterparts to evaluate spontaneous arrhythmias and heart rate variability, a tool to assess autonomic cardiac control. Ventricular function was also evaluated using the pressure-volume conductance system in anesthetized rats. Results Basal RR interval (RRi) was similar between WAR and Wistar rats (188+/-5 vs 199+/-6 ms). RRi variability strongly suggests that WAR present an autonomic imbalance with sympathetic overactivity, which is an isolated risk factor for cardiovascular events. Anesthetized WAR showed lower arterial pressure (92+/-3 vs 115+/-5 mmHg) and exhibited indices of systolic dysfunction, such as higher ventricle end-diastolic pressure (9.2+/-0.6 vs 5.6+/-1 mmHg) and volume (137+/-9 vs 68+/-9 mu L) as well as lower rate of increase in ventricular pressure (5266+/-602 vs 7320+/-538 mmHg.s(-1)). Indices of diastolic cardiac function, such as lower rate of decrease in ventricular pressure (-5014+/-780 vs -7766+/-998 mmHg.s(-1)) and a higher slope of the linear relationship between end-diastolic pressure and volume (0.078+/-0.011 vs 0.036+/-0.011 mmHg.mu L), were also found in WAR as compared to Wistar control rats. Moreover, Wistar rats had 3 to 6 ventricular ectopic beats, whereas WAR showed 15 to 30 ectopic beats out of the 20,000 beats analyzed in each rat. Conclusions The autonomic imbalance observed previously at younger age is also present in aged WAR and, additionally, a cardiac dysfunction was also observed in the rats. These findings make this experimental model of epilepsy a valuable tool to study risk factors for cardiovascular events in epilepsy. (AU)

• Processo FAPESP: 07/50261-4 - Neurociências, epilepsia e arte: caracterização interdisciplinar da cepa WAR e modelos de epilepsia correlacionados: as oficinas Da Vinci, divulgação científica e quebras de estigmas em epilepsia
• Beneficiário: Norberto Garcia Cairasco
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 05/56447-7 - Pesquisa através de imagens por ressonância magnética de alto campo destinadas a estudos em humanos
• Beneficiário: João Pereira Leite
• Modalidade de apoio: Auxílio à Pesquisa - Programa CINAPCE - Temático