BACKGROUND： Oxidative stress plays an important role in the pathophysiology of epilepsy. Glutathione, known as one of the compounds of antioxidant defense, has been shown to inhibit convulsions. Nitric oxide has a pr...BACKGROUND： Oxidative stress plays an important role in the pathophysiology of epilepsy. Glutathione, known as one of the compounds of antioxidant defense, has been shown to inhibit convulsions. Nitric oxide has a proconvulsant effect on a pentylenetetrazole-induced animal model. OBJECTIVE： To evaluate the effects of glutathione administration on nitric oxide levels in brain regions of convulsive and kindling pentylenetetrazole-induced seizure models. DESIGN, TIME, AND SETTING： A randomized, controlled, animal experiment. The study was performed at the Department of Physiology, Gaziantep University and Department of Chemistry-Biochemistry,Kahramamaras Sutcu Imam University in 2006. MATERIALS： Pentylenetetrazole and glutathione were purchased from Sigma, USA. METHODS： A total of 80 mice were assigned to 8 groups （n = 10）： normal control, saline control （1 mL normal saline）, convulsive pentylenetetrazole （single intraperitoneal administration of pentylenetetrazole, 60 mg/kg）, convulsive pentylenetrazole plus glutathione （single administration of 60 mg/kg pentylenetetrazole and 200 mg/kg glutathione）, five-dose glutathione （intraperitoneal injection of 200 mg/kg glutathione respectively at 1, 3, 5, 7, and 10 days）, single-dose glutathione （single administration of 200 mg/kg glutathione）, pentylenetetrazole kindling （intraperitoneal administration of pentylenetetrazole of 40 mg/kg at 1,3, 5, 7, and 10 days）, and pentylenetetrazole kindling plus glutathione group （intraperitoneal injection of 40 mg/kg pentylenetetrazole and 200 mg/kg glutathione respectively at 1, 3, 5, 7, and 10 days）. MAIN OUTCOME MEASURES： All mice were sacrificed 1 hour after the last administration. Brain nitric oxide levels were determined by spectrophotometry. RESULTS： There were no significant differences in nitric oxide levels between the normal control, saline control, five-dose glutathione, and single-dose glutathione groups （P 〉 0.05）. Nitric oxide levels in the cerebral hemisphere and cerebellum were significantly less in the convulsive pentylenetetrazole group, compared with the convulsive pentylenetetrazole plus glutathione group （P 〈 0.01）, and levels in the pentylenetetrazole kindling group were remarkably greater than the remaining groups （P 〈 0.01 ）. Brain nitric oxide levels in all groups gradually decreased from the right brain stem to the left brain stem, cerebellum, left cerebral hemisphere, and right cerebral hemisphere. CONCLUSION： Glutathione regulated nitric oxide levels in various brain regions of pentylenetetrazole-induced kindling models, and did not affect nitric oxide levels in the control mice. These results indicated that glutathione played a role when nitric oxide was over-produced. In addition, the brain stem exhibited the highest levels of nitric oxide in both control mice and pentylenetetrazole-induced kindling models.展开更多
BACKGROUND： In order to study the pathogenesis of iron-induced posttraumatic epilepsy （PTE）, foreign scholars have established several kinds of PTE animal models, among which, the iron- induced PTE animal models pr...BACKGROUND： In order to study the pathogenesis of iron-induced posttraumatic epilepsy （PTE）, foreign scholars have established several kinds of PTE animal models, among which, the iron- induced PTE animal models proposed by Willmore is the most famous. The iron-induced PTE animal models can be established by two methods： one is cortical ferric chloride injection （CFCI） and the other one is pial iontophoresis of ferric chloride （PIFC）. Because Willmore did not give out the elaboration of the behaviors and electroencephalograms （EEGs） of the iron induced PTE animal models established by these two methods, so we have known little about these animal models. OBJECTIVE： To observe the behaviors and EEGs of the iron-induced PTE animal models established by PIFC and CFCI, in order to compare the differences and the study value of these two methods. DESIGN： Qualitative controlled observation tria SETTING： Department of Neurosurgery, Urumqi General Hospital, Lanzhou Military Area Command of Chinese PLA. MATERIALS： Forty healthy adult male SD rats, weighing 200 to 250 g, were involved in this experiment. Reagents and instruments： Ferric chloride （FeCl3·6H2O, Sigma USA）, rat stereotaxic apparatus （ASI company, USA）, the wireless blue tooth electroencephlograms recording system （Nuocheng electric Co.Ltd, Shanghai）, a set of air turbine dental drill unit, dental base acrylic resin powder, microinjector （50 μL）, amperemeter （1 mA）, a pair of batteries, electric resistance （200 kΩ） , variable resistance （100 kΩ）, tubule with endo-meridians of 2 mm （used as import tube）, several silver wire segments and several acupuncture needles were employed in this study. METHODS： This study was carried out in the Experimental Animal Center of the Urumqi General Hospital, Lanzhou Military Area Command of Chinese PLA between November 2004 and April 2005. Establishing the PET animal models by CFCI method： Twenty SD rats were taken, intraperitoneally anesthetized with 50 mg/kg barbanylum and fixed on stereotaxic apparatus. A cranial burr hole with the diameter of 2 mm was drilled 3 mm behind the coronal suture and 2 mm lateral to the sagittal line on the left cranium. Another 5 cranial burr holes with diameter of 2 mm were drilled to place electrodes. The positions of holes were set that taking bregma as original point, sagittal line as Y-axis, the line through the original point and vertical to the Y-axis as X-axis. The unit of the coordinate axis was mm. The coordinate value of the electrodes were （4, 0）, （4, -6）, （-4, 0）, （-4, -6）, at last, a hole with the diameter of 2 mm was drilled on the center of the coronale. 5 μL ferric chloride solution （FeCl3, 100 mmol/L, pH 1.5） was injected into the sensorimotor cortex of rats using microinjector within 5 minutes. The needling depth was 3 mm. The needle was retained for 5 minutes so as to prevent the outflow of liquid. Establishing the PTE animal models by PIFC method： Twenty SD rats were chosen and weighed, and the procedures after weighing were as above.A cranial burr hole with the diameter of 4 mm was drilled in the position where needle inserted in animal models established by CFCI method. Cerebral dura mater was cut. Another 5 holes were drilled to place electrodes in the same position as above. The tip of tubule cotton stuffed inside （to prevent the rapid flow of FeCl3 solution, 100 mmol/L, pH 1.5） was gently connected to cerebral pia mater. The positive and negative electrodes of the amperemeter whose output current was 100 μA were connected to acupuncture needles. The acupuncture needle, which was connected to positive electrode, was inserted into ferric chloride solution, and that which was connected to negative electrode was inserted into the right forelimb of rats subcutaneously. The rats were galvanized for 10 minutes. Record of EEG： The silver wire with blunt anterior extremity was placed on the cerebral dura mater. Then, silver wire and cranial bones were firmly fixed with dental base acrylic resin power. The other side was connected to the wireless blue tooth electroencephlograms recording system to monitor EEG changes. Assessment criteria of seizure degree： Grade Ⅰ ： ＂wet dog-like＂ shudder, facial muscle convulsion and chewing;Grade Ⅱ： rhythmical nodding：Grade Ⅲ： forelimb clonus：Grade Ⅳ： forelimb clonus while standing： Grade Ⅴ： lost the balance, vert, limb＇s convulsion and the whole body＇s tic. MAIN OUTCOME MEASURES： Behaviors and EEGs changes of iron-induced PTE animal models established by PTFC and CFCI. RESULTS： All the 40 rats were involved in the result analysis. （1） The changes of the behaviors： The two animal models both had the epileptic seizures. The epileptic seizure of the animal model established by PIFC mainly presented automatic behavior of chewing, and facial muscle convulsion accompanied with chewing. Epileptic seizure reached the peak within 2.5 to 7 hours after model establishing.It was gradually decreased within 24 hours and hardly seen 1 day after model establishing. The epileptic seizure of the rat model established by CFCI mainly presented turnover upspring and limbs＇ convulsion and urinary incontinence accompanied. The epileptic seizure reached the peak within 3 to 8 hours.It was relatively frequent within 1 week and gradually decreased within 2 weeks after model establishing. The PTE animal models established by CFCI were more closed to clinical PTE process. （2） The form of seizures： The epileptic seizures of the rat model established by PIFC mainly presented grade Ⅰ , seldom presented grades Ⅲ, Ⅳ and Ⅴ; The epileptic seizures of rat model established by CFCI mainly presented the head turning to the right, body＇s rotation, then appeared as grades Ⅳ and Ⅴ, and the whole procedure lasted 1 minute. At the interval of big seizures, grade Ⅰ was observed. From the respect of seizure manifestation, the PTE models established by CFCI were more similar to human PTE. （3） EEGs changes： The sharp waves with average frequency of 9.66 Hz and average amplitude of 183.90 μV were observed on the EEGs of the model established by PIFC when the rats were suffering seizures. The spike waves with average frequency of 16.01 Hz and average amplitude of 143.60 μV were observed on the EEGs of the model established by CFCI when the rats were suffering seizures. CONCLUSTON： （1）Iron-induced PTE rat model is stable and credible. （2）Compared with PTE animal model established by PIFC, PTE animal model established by CFCI is a chronic animal model, and its seizure manifestation is more similar to human PTE. so it is worth further studies.展开更多
BACKGROUND： Electrical stimulation kindling model, having epilepsy-inducing and spontaneous seizure and other advantages, is a very ideal experimental animal model. But the kindling effect might be different at diffe...BACKGROUND： Electrical stimulation kindling model, having epilepsy-inducing and spontaneous seizure and other advantages, is a very ideal experimental animal model. But the kindling effect might be different at different sites. OBJECTIVE： To compare the features of animal models of complex partial epilepsy established through unilateral, bilateral and alternate-side kindling at hippocampus and successful rate of modeling among these 3 different ways. DESIGN： A randomized and controlled animal experiment SETTING： Department of Neurology, Qilu Hospital, Shandong University MATERIALS： Totally 60 healthy adult Wistar rats, weighing 200 to 300 g, of either gender, were used in this experiment. BL-410 biological functional experimental system （Taimeng Science and Technology Co. Ltd, Chengdu） and SE-7102 type electronic stimulator （Guangdian Company, Japan） were used in the experiment. METHODS： This experiment was carried out in the Experimental Animal Center of Shandong University from April to June 2004. After rats were anesthetized, electrode was implanted into the hippocampus. From the first day of measurement of afterdischarge threshold value, rats were given two-square-wave suprathreshold stimulation once per day with 400 μA intensity, 1ms wave length, 60 Hz frequency for 1 s duration. Left hippocampus was stimulated in unilateral kindling group, bilateral hippocampi were stimulated in bilateral kindling group, and left and right hippocampi were stimulated alternately every day in the alternate-side kindling group. Seizure intensity was scored： grade 0： normal, 1： wet dog-like shivering, facial spasm, such as, winking, touching the beard, rhythmic chewing and so on; 2： rhythmic nodding; 3： forelimb spasm;4： standing accompanied by bilateral forelimb spasm;5： tumbling, losing balance, four limbs spasm. Modeling was successful when seizure intensity reached grade 5. t test was used for the comparison of mean value between two samples. MAIN OUTCOME MEASURES： Comparison of the successful rate of modeling, the times of stimulation to reach intensity of grade 5, the lasting time of seizure of grade 3 of rats in each group. RESULTS： Four rats of alternate-side kindling group dropped out due to infection-induced electrode loss, and 56 rats were involved in the result analysis. The successful rate of unilateral kindling group, bilateral kin- dling group and alternate-side kindling group was 55%（11/20）,100%（16/16）and 100%（20/20）, respective- ly. The stimuli to reach the grade 5 spasm were significantly more in the bilateral kindling group than in the unilateral kindling group [（30.63±3.48）, （19.36±3.47）times, t=8.268, P 〈 0.01], and those were significantly fewer in the alternate-side kindling group than in the unilateral kindling group [（ 10.85±1.98）times, t=-8.744, P 〈 0.01]. The duration of grade 3 spasm was significantly longer in the bilateral kindling group than in the unilateral kindling group [（9.75±2.59）, （3.21 ±1.58）days,t=-8.183,P 〈 0.01], Among 20 successful rats of al- ternate-side kindling group, grade 5 spasm was found in the left hippocampi of 11 rats, but grade 3 spasm in their right hippocampi; Grade 5 spasm was found in the right hippocampi of the other 9 rats, grade 4 spasm in the left hippocampus of 1 rat and grade 3 of 8 rats. CONCLUSION ： The speed of establishing epilepsy seizure model by alternate-side kindling is faster than that by unilateral kindling, while that by bilateral kindling is slower than that by unilateral kindling. The successful rate is very high to establish complex partial epilepsy with alternate-side or bilateral kindling. Epilepsy seizure established by alternate-side kindling has antagonistic effect of kindling and the seizure duration of grade 3 spasm is prolonged.展开更多
Partial epilepsy is characterized by recurrent seizures that arise from a localized pathological brain region. During the onset of partial epilepsy, the seizure evolution commonly exhibits typical timescale separation...Partial epilepsy is characterized by recurrent seizures that arise from a localized pathological brain region. During the onset of partial epilepsy, the seizure evolution commonly exhibits typical timescale separation phenomenon. This timescale separation behavior can be mimicked by a paradigmatic model termed as Epileptor, which consists of coupled fast-slow neural populations via a permittivity variable. By incorporating permittivity noise into the Epileptor model, we show here that stochastic fluctuations of permittivity coupling participate in the modulation of seizure dynamics in partial epilepsy. In particular, introducing a certain level of permittivity noise can make the model produce more comparable seizure-like events that capture the temporal variability in realistic partial seizures. Furthermore, we observe that with the help of permittivity noise our stochastic Epileptor model can trigger the seizure dynamics even when it operates in the theoretical nonepileptogenic regime. These findings establish a deep mechanistic understanding on how stochastic fluctuations of permittivity coupling shape the seizure dynamics in partial epilepsy,and provide insightful biological implications.展开更多
文摘BACKGROUND： Oxidative stress plays an important role in the pathophysiology of epilepsy. Glutathione, known as one of the compounds of antioxidant defense, has been shown to inhibit convulsions. Nitric oxide has a proconvulsant effect on a pentylenetetrazole-induced animal model. OBJECTIVE： To evaluate the effects of glutathione administration on nitric oxide levels in brain regions of convulsive and kindling pentylenetetrazole-induced seizure models. DESIGN, TIME, AND SETTING： A randomized, controlled, animal experiment. The study was performed at the Department of Physiology, Gaziantep University and Department of Chemistry-Biochemistry,Kahramamaras Sutcu Imam University in 2006. MATERIALS： Pentylenetetrazole and glutathione were purchased from Sigma, USA. METHODS： A total of 80 mice were assigned to 8 groups （n = 10）： normal control, saline control （1 mL normal saline）, convulsive pentylenetetrazole （single intraperitoneal administration of pentylenetetrazole, 60 mg/kg）, convulsive pentylenetrazole plus glutathione （single administration of 60 mg/kg pentylenetetrazole and 200 mg/kg glutathione）, five-dose glutathione （intraperitoneal injection of 200 mg/kg glutathione respectively at 1, 3, 5, 7, and 10 days）, single-dose glutathione （single administration of 200 mg/kg glutathione）, pentylenetetrazole kindling （intraperitoneal administration of pentylenetetrazole of 40 mg/kg at 1,3, 5, 7, and 10 days）, and pentylenetetrazole kindling plus glutathione group （intraperitoneal injection of 40 mg/kg pentylenetetrazole and 200 mg/kg glutathione respectively at 1, 3, 5, 7, and 10 days）. MAIN OUTCOME MEASURES： All mice were sacrificed 1 hour after the last administration. Brain nitric oxide levels were determined by spectrophotometry. RESULTS： There were no significant differences in nitric oxide levels between the normal control, saline control, five-dose glutathione, and single-dose glutathione groups （P 〉 0.05）. Nitric oxide levels in the cerebral hemisphere and cerebellum were significantly less in the convulsive pentylenetetrazole group, compared with the convulsive pentylenetetrazole plus glutathione group （P 〈 0.01）, and levels in the pentylenetetrazole kindling group were remarkably greater than the remaining groups （P 〈 0.01 ）. Brain nitric oxide levels in all groups gradually decreased from the right brain stem to the left brain stem, cerebellum, left cerebral hemisphere, and right cerebral hemisphere. CONCLUSION： Glutathione regulated nitric oxide levels in various brain regions of pentylenetetrazole-induced kindling models, and did not affect nitric oxide levels in the control mice. These results indicated that glutathione played a role when nitric oxide was over-produced. In addition, the brain stem exhibited the highest levels of nitric oxide in both control mice and pentylenetetrazole-induced kindling models.
文摘BACKGROUND： In order to study the pathogenesis of iron-induced posttraumatic epilepsy （PTE）, foreign scholars have established several kinds of PTE animal models, among which, the iron- induced PTE animal models proposed by Willmore is the most famous. The iron-induced PTE animal models can be established by two methods： one is cortical ferric chloride injection （CFCI） and the other one is pial iontophoresis of ferric chloride （PIFC）. Because Willmore did not give out the elaboration of the behaviors and electroencephalograms （EEGs） of the iron induced PTE animal models established by these two methods, so we have known little about these animal models. OBJECTIVE： To observe the behaviors and EEGs of the iron-induced PTE animal models established by PIFC and CFCI, in order to compare the differences and the study value of these two methods. DESIGN： Qualitative controlled observation tria SETTING： Department of Neurosurgery, Urumqi General Hospital, Lanzhou Military Area Command of Chinese PLA. MATERIALS： Forty healthy adult male SD rats, weighing 200 to 250 g, were involved in this experiment. Reagents and instruments： Ferric chloride （FeCl3·6H2O, Sigma USA）, rat stereotaxic apparatus （ASI company, USA）, the wireless blue tooth electroencephlograms recording system （Nuocheng electric Co.Ltd, Shanghai）, a set of air turbine dental drill unit, dental base acrylic resin powder, microinjector （50 μL）, amperemeter （1 mA）, a pair of batteries, electric resistance （200 kΩ） , variable resistance （100 kΩ）, tubule with endo-meridians of 2 mm （used as import tube）, several silver wire segments and several acupuncture needles were employed in this study. METHODS： This study was carried out in the Experimental Animal Center of the Urumqi General Hospital, Lanzhou Military Area Command of Chinese PLA between November 2004 and April 2005. Establishing the PET animal models by CFCI method： Twenty SD rats were taken, intraperitoneally anesthetized with 50 mg/kg barbanylum and fixed on stereotaxic apparatus. A cranial burr hole with the diameter of 2 mm was drilled 3 mm behind the coronal suture and 2 mm lateral to the sagittal line on the left cranium. Another 5 cranial burr holes with diameter of 2 mm were drilled to place electrodes. The positions of holes were set that taking bregma as original point, sagittal line as Y-axis, the line through the original point and vertical to the Y-axis as X-axis. The unit of the coordinate axis was mm. The coordinate value of the electrodes were （4, 0）, （4, -6）, （-4, 0）, （-4, -6）, at last, a hole with the diameter of 2 mm was drilled on the center of the coronale. 5 μL ferric chloride solution （FeCl3, 100 mmol/L, pH 1.5） was injected into the sensorimotor cortex of rats using microinjector within 5 minutes. The needling depth was 3 mm. The needle was retained for 5 minutes so as to prevent the outflow of liquid. Establishing the PTE animal models by PIFC method： Twenty SD rats were chosen and weighed, and the procedures after weighing were as above.A cranial burr hole with the diameter of 4 mm was drilled in the position where needle inserted in animal models established by CFCI method. Cerebral dura mater was cut. Another 5 holes were drilled to place electrodes in the same position as above. The tip of tubule cotton stuffed inside （to prevent the rapid flow of FeCl3 solution, 100 mmol/L, pH 1.5） was gently connected to cerebral pia mater. The positive and negative electrodes of the amperemeter whose output current was 100 μA were connected to acupuncture needles. The acupuncture needle, which was connected to positive electrode, was inserted into ferric chloride solution, and that which was connected to negative electrode was inserted into the right forelimb of rats subcutaneously. The rats were galvanized for 10 minutes. Record of EEG： The silver wire with blunt anterior extremity was placed on the cerebral dura mater. Then, silver wire and cranial bones were firmly fixed with dental base acrylic resin power. The other side was connected to the wireless blue tooth electroencephlograms recording system to monitor EEG changes. Assessment criteria of seizure degree： Grade Ⅰ ： ＂wet dog-like＂ shudder, facial muscle convulsion and chewing;Grade Ⅱ： rhythmical nodding：Grade Ⅲ： forelimb clonus：Grade Ⅳ： forelimb clonus while standing： Grade Ⅴ： lost the balance, vert, limb＇s convulsion and the whole body＇s tic. MAIN OUTCOME MEASURES： Behaviors and EEGs changes of iron-induced PTE animal models established by PTFC and CFCI. RESULTS： All the 40 rats were involved in the result analysis. （1） The changes of the behaviors： The two animal models both had the epileptic seizures. The epileptic seizure of the animal model established by PIFC mainly presented automatic behavior of chewing, and facial muscle convulsion accompanied with chewing. Epileptic seizure reached the peak within 2.5 to 7 hours after model establishing.It was gradually decreased within 24 hours and hardly seen 1 day after model establishing. The epileptic seizure of the rat model established by CFCI mainly presented turnover upspring and limbs＇ convulsion and urinary incontinence accompanied. The epileptic seizure reached the peak within 3 to 8 hours.It was relatively frequent within 1 week and gradually decreased within 2 weeks after model establishing. The PTE animal models established by CFCI were more closed to clinical PTE process. （2） The form of seizures： The epileptic seizures of the rat model established by PIFC mainly presented grade Ⅰ , seldom presented grades Ⅲ, Ⅳ and Ⅴ; The epileptic seizures of rat model established by CFCI mainly presented the head turning to the right, body＇s rotation, then appeared as grades Ⅳ and Ⅴ, and the whole procedure lasted 1 minute. At the interval of big seizures, grade Ⅰ was observed. From the respect of seizure manifestation, the PTE models established by CFCI were more similar to human PTE. （3） EEGs changes： The sharp waves with average frequency of 9.66 Hz and average amplitude of 183.90 μV were observed on the EEGs of the model established by PIFC when the rats were suffering seizures. The spike waves with average frequency of 16.01 Hz and average amplitude of 143.60 μV were observed on the EEGs of the model established by CFCI when the rats were suffering seizures. CONCLUSTON： （1）Iron-induced PTE rat model is stable and credible. （2）Compared with PTE animal model established by PIFC, PTE animal model established by CFCI is a chronic animal model, and its seizure manifestation is more similar to human PTE. so it is worth further studies.
文摘BACKGROUND： Electrical stimulation kindling model, having epilepsy-inducing and spontaneous seizure and other advantages, is a very ideal experimental animal model. But the kindling effect might be different at different sites. OBJECTIVE： To compare the features of animal models of complex partial epilepsy established through unilateral, bilateral and alternate-side kindling at hippocampus and successful rate of modeling among these 3 different ways. DESIGN： A randomized and controlled animal experiment SETTING： Department of Neurology, Qilu Hospital, Shandong University MATERIALS： Totally 60 healthy adult Wistar rats, weighing 200 to 300 g, of either gender, were used in this experiment. BL-410 biological functional experimental system （Taimeng Science and Technology Co. Ltd, Chengdu） and SE-7102 type electronic stimulator （Guangdian Company, Japan） were used in the experiment. METHODS： This experiment was carried out in the Experimental Animal Center of Shandong University from April to June 2004. After rats were anesthetized, electrode was implanted into the hippocampus. From the first day of measurement of afterdischarge threshold value, rats were given two-square-wave suprathreshold stimulation once per day with 400 μA intensity, 1ms wave length, 60 Hz frequency for 1 s duration. Left hippocampus was stimulated in unilateral kindling group, bilateral hippocampi were stimulated in bilateral kindling group, and left and right hippocampi were stimulated alternately every day in the alternate-side kindling group. Seizure intensity was scored： grade 0： normal, 1： wet dog-like shivering, facial spasm, such as, winking, touching the beard, rhythmic chewing and so on; 2： rhythmic nodding; 3： forelimb spasm;4： standing accompanied by bilateral forelimb spasm;5： tumbling, losing balance, four limbs spasm. Modeling was successful when seizure intensity reached grade 5. t test was used for the comparison of mean value between two samples. MAIN OUTCOME MEASURES： Comparison of the successful rate of modeling, the times of stimulation to reach intensity of grade 5, the lasting time of seizure of grade 3 of rats in each group. RESULTS： Four rats of alternate-side kindling group dropped out due to infection-induced electrode loss, and 56 rats were involved in the result analysis. The successful rate of unilateral kindling group, bilateral kin- dling group and alternate-side kindling group was 55%（11/20）,100%（16/16）and 100%（20/20）, respective- ly. The stimuli to reach the grade 5 spasm were significantly more in the bilateral kindling group than in the unilateral kindling group [（30.63±3.48）, （19.36±3.47）times, t=8.268, P 〈 0.01], and those were significantly fewer in the alternate-side kindling group than in the unilateral kindling group [（ 10.85±1.98）times, t=-8.744, P 〈 0.01]. The duration of grade 3 spasm was significantly longer in the bilateral kindling group than in the unilateral kindling group [（9.75±2.59）, （3.21 ±1.58）days,t=-8.183,P 〈 0.01], Among 20 successful rats of al- ternate-side kindling group, grade 5 spasm was found in the left hippocampi of 11 rats, but grade 3 spasm in their right hippocampi; Grade 5 spasm was found in the right hippocampi of the other 9 rats, grade 4 spasm in the left hippocampus of 1 rat and grade 3 of 8 rats. CONCLUSION ： The speed of establishing epilepsy seizure model by alternate-side kindling is faster than that by unilateral kindling, while that by bilateral kindling is slower than that by unilateral kindling. The successful rate is very high to establish complex partial epilepsy with alternate-side or bilateral kindling. Epilepsy seizure established by alternate-side kindling has antagonistic effect of kindling and the seizure duration of grade 3 spasm is prolonged.
基金supported by the National Natural Science Foundation of China(Grant Nos.81571770,61527815,81371636 and 81330032)
文摘Partial epilepsy is characterized by recurrent seizures that arise from a localized pathological brain region. During the onset of partial epilepsy, the seizure evolution commonly exhibits typical timescale separation phenomenon. This timescale separation behavior can be mimicked by a paradigmatic model termed as Epileptor, which consists of coupled fast-slow neural populations via a permittivity variable. By incorporating permittivity noise into the Epileptor model, we show here that stochastic fluctuations of permittivity coupling participate in the modulation of seizure dynamics in partial epilepsy. In particular, introducing a certain level of permittivity noise can make the model produce more comparable seizure-like events that capture the temporal variability in realistic partial seizures. Furthermore, we observe that with the help of permittivity noise our stochastic Epileptor model can trigger the seizure dynamics even when it operates in the theoretical nonepileptogenic regime. These findings establish a deep mechanistic understanding on how stochastic fluctuations of permittivity coupling shape the seizure dynamics in partial epilepsy,and provide insightful biological implications.
