Avaliação de parâmetros cardíacos em animais com epilepsia: possível causa de morte súbita?

Abstract

Dentre as causas de morte súbita nas epilepsias (SUDEPE), as disfunções cardíacas têm sido uma área de interesse. Sendo assim, o objetivo de nosso estudo foi avaliar a freqüência cardíaca (FC) (in vivo e in vitro) e a pressão ventricular (PV) in vitro de ratos com epilepsia induzida pela pilocarpina. Ratos machos, adultos, da raça Wistar (n=6) receberam pilocarpina para a indução do status epilepticus. Ratos controles (n=6) receberam solução salina ao invés de pilocarpina. Nossos resultados mostram diferenças significantes na freqüência cardíaca in vivo entre os grupos estudados. Em contraste, não encontramos diferenças entre os grupos nos experimentos in vitro. Nossos resultados sugerem que sob a influência do sistema nervoso central, o coração pode apresentar alterações funcionais que aumentam a probabilidade de ocorrência de morte súbita nas epilepsias.

Sudden unexpected death in epilepsy and the song of science

“…Quite SUDEP: the song of science Scorza interesting, we did not find differences in the isolated ex vivo situation (control animals: 175±7 bpm; animals with epilepsy: 176±6 bpm), suggesting that autonomic modulation of the heart is changed in rats with epilepsy, which could explain the appearance and maintenance of an increased basal heart rate in these animals 10 . Recently, we also analyzed heart rate in rats subjected to electrical kindling of the amygdala 11 .…”

“…Following this line of reasoning, the experience of our research group makes us increasingly believe that some chronic models of temporal lobe epilepsy are important tools for the study of cardiovascular abnormalities in epilepsy and may even be relevant for the understanding of the SUDEP phenomenon. In 2005, we used the pilocarpine model in order to evaluate the heart rate from rats with epilepsy in vivo (ECG) and in an isolated ex vivo preparation (Langendorf preparation) 10 . In brief,…”

The number and periodicity of seizures induce cardiac remodeling and changes in micro-RNA expression in rats submitted to electric amygdala kindling model of epilepsy

“…Several clinical and experimental studies have shown important changes in cardiovascular parameters, such as HR, blood pressure, electrocardiography, and levels of circulating catecholamines during the ictal and interictal periods [25]. The exact mechanism of these changes still needs to be clarified, but it seems to be strongly related to autonomic modulation, which was seen by Colugnati et al [26] who found that the increased resting HR of pilocarpine-induced epileptic rats was not due to intrinsic dysfunction. Our study corroborates this finding, since no differences were found in the intrinsic HR of rats with epilepsy, regardless of seizure frequency.…”