Mohammad Javan; Seyyed Javad Mirnajafizadeh; Maryam Zeraati; Simin Namvar
Volume 17, Issue 3 , September and October 2010, , Pages 158-169
Abstract
Background and Purpose: Despite widespread research on epilepsy, the mechanism of its insidnece is still unknown. Since the activity of ATPase plays a vital role in changing ATP into AMP, and this substance can later turn into adenosine which is the most important endogenous anticonvulsant agent in brain, ...
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Background and Purpose: Despite widespread research on epilepsy, the mechanism of its insidnece is still unknown. Since the activity of ATPase plays a vital role in changing ATP into AMP, and this substance can later turn into adenosine which is the most important endogenous anticonvulsant agent in brain, the effect of inhibition of ATPase on perforant path kindling was investigated in the present study. Methods and Materials: In this experimental study, animals were kindled by electrical stimulations of the perforant path (12 times a day with a frequency of 50 Hz and pulse duration of 1 millisecond). Upon kindling, behavioral and electrophysiologic measures of convulsions and filed potentials were recorded. For investigating the role of ATPase in animal groups, FPL 67156 was injected as the inhibitor of the ATPase after kindling stimulations ended each day. Kindled animals were 6, and there were 4 rats in other groups. Repeated measures ANOVA and Bonferoni test were used to compare the statistical quantities of fEPSP and PS of epilepsy creation in different groups of the study. Comparing the difference of paired pulses between groups was conducted by Bonferoni test. The five-stage convulsion of the groups was compared through Kruskall Wallis and Mann Whitney U tests. Statistical analyses were conducted in Prism 5. Results: The results indicated that ATPase inhibition (by injecting FPL 67156) causes no change in various behavioral stages of convulsion and daily afterdischarge duration following kindling (P>0.05); however, it affects synapsis formation, so that PS increases in comparison with the kindled group (P
Seyyed Javad Mirnajafizadeh; Ali Jahanshahi Anvar; Yosef Sadeghi; Raziyeh Rohani; Abbas Piriayi; Maryam Zeraati
Volume 17, Issue 2 , July and August 2010, , Pages 96-107
Abstract
Background and Purpose: Application of low-frequency stimulation (LFS) induces anticonvulsant effects. In this study, the effect of changes in LFS frequencies on its anticonvulsant effects in kindling model of epilepsy was investigated by determining the behavioral and ultrastructural changes. Methods ...
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Background and Purpose: Application of low-frequency stimulation (LFS) induces anticonvulsant effects. In this study, the effect of changes in LFS frequencies on its anticonvulsant effects in kindling model of epilepsy was investigated by determining the behavioral and ultrastructural changes. Methods and Materials: In this experimental study, 45 Wistar rats weighing 250-280 g were used. For induction of kindled seizures, stimulating and recording electrodes were implanted in perforant path and dentate gyrus respectively. Animals were stimulated in a rapid kindling manner. Different groups of animals received LFS at different frequencies (0.5, 1 and 5 Hz) following kindling stimulations and their effects on kindling rate were determined using behavioral and electrophysiological studies. After stimulating the animals for 7 days, they were killed and their dentate gyri were sampled for ultrastructural studies under electron microscopy. For data analysis, one-way and two-way ANOVA, LSD, Kruskal Wallis and Mann Whitney U were used in Statistica 2. Results: Different LFS frequencies had a significant inhibitory effect on kindling rate and decreased after-discharge duration and the number of stimulations to achieve stage 4 and 5 seizures significantly. In addition, application of LFS prevented the increase in the post-synaptic density and induction of concave synaptic vesicles following kindling. There was not any significant change between anticonvulsant effects of LFS at different frequencies. Conclusion: Obtained results show that LFS application can prevent the neuronal hyper-excitability by preventing the ultrastructural changes during kindling, and can exert its anticonvulsant effects.