Quantitative Analysis of the Antiepileptogenic Effects of Low Frequency Stimulation Applied Prior or After Kindling Stimulation in Rats

Background and Objective: Developing quantitative measures based on spectral analysis of electroencephalograph (EEG) recordings of neural activities plays an important role in developing efficient treatments for epilepsy. Such biomarkers can be used for developing open or closed loop approaches for seizure prediction or prevention. This study aims to quantitatively evaluate antiepileptogenic effects of low frequency stimulation (LFS) applied immediately before or after kindling stimulations using spectral power analysis of extracellular EEG in rat.Methods: Nineteen adult rats were used: seven for kindle, six for LFS+Kindle (LFSK) and six for Kindle+LFS (KLFS). Four packages of LFS (1Hz) were applied immediately before or after rapid kindling stimulations. The power spectral densities of afterdischarge (AD) sections of EEG corresponding to different stages of kindling for delta (0–4 Hz), theta (4–8 Hz), alpha (8–12 Hz), beta (12–28 Hz), gamma (28–40 Hz) sub-bands, and theta/alpha ratio were comparatively investigated. Moreover, correlation between AD duration (ADD) and its different frequency components was calculated.Results: Both LFSK and KLFS significantly increased delta and reduced beta and gamma oscillations, compared with kindle group. However, just the reduction in LFSK group was significant. Both protocols increased theta/alpha ratio, but just LFSK showed significant increase (p < 0.05). Although LFSK enhanced theta/alpha ratio more than KLFS, the difference was not statistically significant. Furthermore, strong correlation between each frequency sub band and ADD was not observed in kindle and LFS treated groups (both LFSK and KLFS).Conclusion: Although behavioral assessments showed relatively the same level of antiepileptogenic effects for KLFS and LFSK, quantitative assessments showed more significant differences in the quantitative measures between the two protocols. Developing more quantitative EEG based measures correlated with LFS-induced effects can facilitate developing open or closed loop seizure prevention modalities

The effect of electrical low-frequency stimulation on balance and locomotor activity in adult male rats during epileptogenesis of dorsal hippocampal

Background: Epilepsy is the third world neurological disorder. Epileptic focus causes motor impairment by sending projections to different areas of the brain such as areas which are related to movement control. Regarding the inhibitory effect of low-frequency electrical stimulation (LFS) on seizure wave's transmission, this study aimed at examining the effect of LFS during the epileptogenesis of dorsal hippocampal on balance and locomotor activity in adult male rats using the kindling method. Materials and Methods: Fifty rats were randomly divided into 5 groups: Control, Sham, Kindled, LFS and KLFS. Animals in the kindled group were stimulated rapidly by daily stimulation of dorsal hippocampus (1 ms pulse duration at 50Hz for 3 seconds). Animals in the sham and control groups did not receive any stimulation. In the LFS groups, four LFS packages at a frequency of 1 Hz were applied daily. At the end of stimulation, motor activity and balance were assessed by open-field and rotarod tests. Results: Frequency of rearing and grooming in the Kindled group significantly increased compared to the control group (P<0.05). Balance in the Kindled group was significantly decreased (P<0.05). LFS induction during hippocampal kindling did not show any significant difference in any of the mentioned parameters with the control group. Conclusion: In summary, applying low-frequency electrical stimulation during hippocampal kindling can reduce the motor activity and improve balance

Effect of co-administration of donepezil and folic acid on spatial memory impairment in adult male rat model of Alzheimer's disease

Background: Alzheimer's disease is a neurodegenerative disorder that is diagnosed with a lack of memory and perception. Objective: The aim of this study was to evaluate the effect of donepezil and folic acid on reference and working memory disorders caused by electrical lesion of nucleus basalis magnocellularis (NBM). Methods: In this experimental study, 49 adult male Wistar rats were divided into 7 groups: control and, nucleus basalis magnocellularis (NBM) lesion group. which received electrically-induced lesion (0.5 mA, 3 s) in NBM, sham group (the electrode was impaled in to the nucleus basalis magnocellularis with no lesion), donepezil group (lesion + donepezil 0.1 mg/kg), folic acid group (lesion + folic acid 5 mg), interaction group (lesion + donepezil-folic acid) and vehicle group (lesion + saline). Acquisition and retention tests were done by using an eight-radial arm maze task. Findings: Results showed that there was a significant difference between control and lesion groups (P<0.05). Combination treatment with donepezil and folic acid improved the parameters of spatial memory errors in the acquisition and retention tasks comparing to the control group (P˂0.05). Conclusion: The degradation of the nucleus basalis magnocellularis caused to increase reference and working memory errors. Also the co-administration of donepezil and folic acid leaded to a reduction in these errors and improved spatial memory of the rat

Effect of co-administration of lovastatin and folic acid on cognitive impairment due to bilateral electrical lesion of nucleus basalis magnocellularis in the Alzheimer\'s disease model in adult male rats

Introduvtion: Alzheimer's disease is one of the most common neurodegenerative diseases in the brain. The aim of this study was to evaluate the effect of lovastatin and folic acid on cognitive deficit by induced lesion in nucleus basalis magnocellularis Methods: In this experimental study, 56 male Wistar rats were randomly divided into 8 groups: (7 rat in each group): control(intact), Nucleus basalis magnocellularis (NBM) lesion group, which received electrically- induced lesion (0.5 m A, 3s) in NBM, Sham group ( the electrode was impaled in to the NBM with no lesion), lovastatin group (NBM lesion + lovastatin 1mg/kg), folic acid group (NBM lesion+ folic acid 5mg/kg), interaction group( NBM lesion+ lovastatin-folic acid), saline group( NBM lesion + saline) and Dimethyl sulfoxide (DMSO) group (NBM lesion + DMSO 5%). Acquisition and retention testing was done by using an eight-radial arm maze, in which, the patterns of arm entries in each group for calculating working memory errors, reference memory error and latency were recorded. Data were analyzed using one-way ANOVA and Tukey's post hoc test Results: Results showed that there was a significant difference between the control and lesion groups in the parameters of the reference memory error, working memory error and elapsed time (P˂ 0.05). Co-administration of&nbsp; lovastatin - folic acid resulted in a reduction in the reference and working memory error and the time spent in the eight-arm radial laser maze compared with lesion group Conclusion: According to the results, co-administration of folic acid and lovastatin had a positive effect on spatial memory of Alzheimer's rats

Long-term effects of maternal exposure to Di (2-ethylhexyl) Phthalate on sperm and testicular parameters in Wistar rats offspring

Background: Phthalate esters have been shown to cause reproductive toxicity in both developing and adult animals. Objective: This study was designed to assess long-term effects of maternal exposure to Di (2-ethylhexyl) Phthalate (DEHP) on reproductive ability of both neonatal and adult male offspring.Materials and Methods: 60 female rats randomly divided in four equal groups; vehicle control and three treatment groups that received 10, 100 and 500 mg/kg/day DEHP via gavage during gestation and lactation. At different ages after birth, the volumes of testes were measured by Cavellieri method, testes weights recorded and epididymal sperm samples were assessed for number and gross morphology of spermatozoa. Following tissue processing, seminiferous tubules diameter and germinal epithelium height evaluated with morphometric techniques.Results: Mean testis weight decreased significantly (p<0.05) in 500 mg/kg/day dose group from 28 to 150 days after birth. Significant decreases were seen in total volumes of testis in 100 (p<0.05) and 500 (p<0.01) mg/kg/day doses groups until 150 days after birth. Seminiferous tubules diameter and germinal epithelium height decreased significantly in 100 (p<0.05) and 500 (p<0.01) mg/kg/day doses groups during postnatal development. Also, mean sperm density in 100 mg/kg/day (p<0.05) and 500 mg/kg/day (p<0.01) doses groups and percent of morphologically normal sperm in highest dose group (p<0.05) decreased significantly until 150 days after birth. Conclusion: Present study showed that maternal exposure to Di (2-ethylhexyl) Phthalate during gestation and lactation caused to permanent and dose-related reductions of sperm and testicular parameters in rats offsprin

Low Frequency Electrical Stimulation Either Prior to Or after Rapid Kindling Stimulation Inhibits the Kindling-Induced Epileptogenesis

Objective. Studies are ongoing to find appropriate low frequency stimulation (LFS) protocol for treatment of epilepsy. The present study aimed at assessing the antiepileptogenesis effects of LFS with the same protocol applied either just before or immediately after kindling stimulations. Method. This experimental animal study was conducted on adult Wistar rats (200 ± 20 g) randomly divided into kindle (n=7), LFS + Kindle (n=6), and Kindle + LFS groups (n=6). All animals underwent rapid kindling procedure and four packages of LFS (1 Hz) with 5 min interval were applied either immediately before (LFS-K) or after kindling stimulation (K-LFS). The after discharge duration (ADD), daily stages of kindling, and kindling seizure stage and number of stimulations required to reach each stage were compared between the three groups using two-way analysis of variance (ANOVA) followed by Tukey post hoc and one-way ANOVA, and Kruskal-Wallis test, respectively. Results. LFS in both protocols significantly decreased the ADD (p0.05, stages 3 to 5: p<0.05). Conclusion. Although LFS-K showed more inhibiting effect than K-LFS, the difference was not statistically significant

The Effect of Acute and Chronic Sesame Oil Consumption on the Strychnine Induced Seizure in Adult Rats

Background & objectives: Diet plays an important role in control of seizure in epileptic patients. Therefore in this research, the effect of acute and chronic sesame oil consumption on the seizure induced by strychnine in adult rats was investigated. Methods: In this experimental study, forty -two rats were divided into six groups: control (saline recipient, 1 ml/kg (, acute recipients of sodium valproate as positive control group (100 or 200 mg/kg, ip.), acute recipients of sesame oil (0.75 or 1.5 ml/kg, ip.) and chronic recipient of sesame oil (1.5 ml/kg/day, orally, 21 days). To induce seizure, strychnine was injected intraperitoneally 30 minutes after receiving saline, valproate or oil. Then seizure onset time and death time were recorded within 30 minutes. Results: Acute injection of sesame oil increased seizure onset time and death time compared to control group but it was no significantly different. The chronic consumption of sesame oil significantly increased seizure onset time (p=0.029) in compared to control group, but there was no effect on the death time. Also, there were no significant differences in seizure onset time and death time between acute and chronic groups. Conclusion: It seems that chronic consumption of sesame oil delayed the onset of seizure and reduced the kindled seizure acquisition