ABSTRACT
Calcium ion participates in the regulation of neural transmission and the presynaptic release of neurotransmitters. It is also involved in epileptic events, cardiac arrhythmias and abnormal conduction of stimuli. The purpose of the present study was to evaluate the effects of nifedipine, a calcium channel blocker, on epileptic seizures and on reperfusion arrhythmias in rats prone to audiogenic epileptic seizures (Wistar audiogenic rats, WAR) and in normal Wistar rats (N = 6/group). The seizure severity index was applied after an intraperitoneal injection of 20 or 40 mg/kg nifedipine (N20 and N40 groups, respectively). The Langendorff technique was used to analyze cardiac function, as well as the incidence and severity of the reperfusion arrhythmias after ligature and release of the left coronary artery in rats treated or not with nifedipine. We found that nifedipine treatment decreased seizure severity (0.94 ± 0.02 for WAR; 0.70 ± 0.10 for WAR + N20; 0.47 ± 0.08 for WAR + N40) and increased the latent period (13 ± 2 s for WAR; 35 ± 10 s for WAR + N20; 48 ± 7 s for WAR + N40) for the development of seizures in WAR. Furthermore, the incidence and severity of the reperfusion arrhythmias were lower in WAR and normal Wistar rats injected with nifedipine. In WAR, these effects were mediated, at least in part, by a decrease in heart rate. Thus, our results indicate that nifedipine may be considered to be a potential adjuvant drug for epilepsy treatment, especially in those cases associated with cardiac rhythm abnormalities.
Subject(s)
Animals , Male , Rats , Anti-Arrhythmia Agents/therapeutic use , Anticonvulsants/therapeutic use , Arrhythmias, Cardiac/drug therapy , Nifedipine/therapeutic use , Seizures/drug therapy , Acoustic Stimulation , Disease Models, Animal , Electrocardiography , Epilepsy, Reflex , Rats, Wistar , Severity of Illness IndexABSTRACT
Este trabalho objetivou verificar os efeitos da aplicação aguda endovenosa dos extratos hidroalcoólicos de Allium sativum e de Cymbopogon citratus sobre a pressão arterial de ratos. Foram usados Rattus novergicus albinus, n=7, anestesiados, traqueostomizados e canulados através da veia jugular e da artéria carótida. Foram injetadas doses de 1 mg dos extratos separadamente e em associação (1mg + 1mg), em volumes de 0,2mL. A pressão arterial média (PAM) foi registrada com um sistema Biopac, modelo MP100. O Allium sativum diminuiu a PAM de 124±2 mmHg, no controle, para 108±2 mmHg aos 15s. Da mesma forma, o Cymbopogon citratus diminuiu a PAM de 122±2 mmHg, no controle, para 106± 2 mmHg aos 15s. A associação de ambos também diminuiu a PAM de 126±3 mmHg, no controle, para 113±3 mmHg aos 15s. Os efeitos das duas plantas foram iguais e não foram incrementados quando associadas.
This work aimed to verify the effects of acute intravenous applications of Allium sativum and Cymbopogon citratus hydroalcoholic extracts on arterial blood pressure of anesthetized rats. Adult male rats (Rattus novergicus albinus), n=7, were used. The rats were anesthetized, tracheotomy and cannulation of both jugular and carotid were carried out. The injected doses were 1 mg separately as well as the association of both extracts, in volumes of 0,2 mL. The mean arterial blood pressure (MAP) was recorded with a Biopac System, model MP100. The Allium sativum decreased the MAP only from 124±2 mmHg (control) to 108±2 mmHg at 15s. The Cymbopogon citratus also decreased the MAP from 122±2 mmHg (control) to 106±2 mmHg after 15s. The 1mg of Allium sativum + 1mg of Cymbopogon citratus also decreased the MAP from 126±3 mmHg (control) to 113±3 mmHg after 15s. The effects of the two plants were the same and were not increased when in association.