Anticonvulsant and antiarrhythmic effects of nifedipine in rats prone to audiogenic seizures

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.

Cardiac dysfunction in rats prone to audiogenic epileptic seizures

“…The coronary flow was measured by collecting the perfusate over a period of 1 min at regular intervals. 23 The hearts were perfused for an initial 30-min period with KRS under sinusal rhythm. At the end of this time, a ligature was placed around the left anterior descending (LAD) coronary artery close to its origin.…”

Cardiovascular dysautonomia after seizures induced by maximal electroshock in Wistar rats

“…The coronary flow was measured by collecting the perfusate over a period of one minute at regular intervals. 16 The hearts were perfused for an initial 30-min period with KRS under sinusal rhythm. At the end of this time, a ligature was placed around the left anterior descending (LAD) coronary artery close to its origin.…”

Combined anticonvulsant effect of nifedipine and pentazocine in experimentally induced seizures in rats

“…7 In view of promising results with pentazocine, the screening and evaluation of highly selective kappa opioid drugs may prove beneficial to the development of novel therapeutic approaches to epilepsy. [8][9][10] This combination therapy may have important potential, especially in those patients in whom conventional therapy has been inadequate or in patients who are refractory to anticonvulsant treatment , or in cases of in treatable epilepsy. 11,12 Thus, on the basis of present data and other studies it can be said that nifedipine in combination with pentazocine may be effective against partial and generalized tonic clonic seizures.…”