Epileptic Rat Model Research Articles

Sodium Valproate Ameliorates Neuronal Apoptosis in a Kainic Acid Model of Epilepsy via Enhancing PKC-Dependent GABAAR γ2 Serine 327 Phosphorylation.

GABA is a dominant inhibitory neurotransmitter in the brain and A type GABA receptor (GABAAR) phosphorylation is critical for GABA-mediated inhibitory effect. However, its role in the neuroprotective effect of sodium valproate (VPA), a prevalent drug for treating patients with epilepsy, remains elusive. The present study was conducted to explore the role of GABAAR phosphorylation in the neuroprotection of VPA against a kainic acid-induced epileptic rat model and the potential molecular mechanisms. Neuronal apoptosis was evaluated by TUNEL assay, PI/Annexin V double staining, caspase-3 activity detection and Bax and Bcl-2 proteins expression via Western blot analysis. The primary rat hippocampal neurons were cultivated and cell viability was measured by CCK8 detection following KA- or free Mg2+-induced neuronal impairment. Our results found that VPA treatment significantly reduced neuronal apoptosis in the KA-induced rat model (including reductions of TUNEL-positive cells, caspase-3 activity and Bax protein expression, and increase of Bcl-2 protein level). In the in vitro experiments, VPA at the concentration of 1mM for 24h also increased cell survival and suppressed cell apoptosis in KA- or no Mg2+-induced models via CCK8 assay and PI/Annexin V double staining, respectively. What is more important, the phosphorylation of γ2 subunit at serine 327 residue for GABAAR was found to be robustly enhanced both in the KA-induced epileptic rat model and neuronal cultures following KA exposure after VPA treatment, while no evident alteration was found in terms of GABAAR β3 phosphorylation (408 or 409 serine residue). Additionally, pharmacological inhibition of protein kinase C (PKC) clearly abrogated the neuroprotective potential of VPA against KA- or free Mg2+-associated neuronal injury, indicating a critical role of PKC in the effect of GABAAR γ2 serine 327 phosphorylation in VPA's protection. In summary, our work reveals that VPA mitigates neuronal apoptosis in KA-triggered epileptic seizures, at least, via augmenting PKC-dependent GABAAR γ2 phosphorylation at serine 327 residue.

Curcumin Reduces Neuronal Loss and Inhibits the NLRP3 Inflammasome Activation in an Epileptic Rat Model.

Background: Epilepsy is a chronic neurological disorder affecting an estimated 50 mil-lion people worldwide. Emerging evidences have accumulated over the past decades supporting the role of inflammation in the pathogenesis of epilepsy. Curcumin is a nature-derived active molecule demonstrating anti-inflammation efficacy. However, its effects on epilepsy and corresponding mech-anisms remain elusive.Objective: To investigate the effects of curcumin on epilepsy and its underlying mechanism.Method: Forty Sprague Dawley rats were divided into four groups: (1) control group; (2) Kainic Acid (KA)-induced epilepsy group; (3) curcumin group; and (4) curcumin pretreatment before KA stimulation group. Morris water maze was utilized to assess the effect of curcumin on KA-induced epilepsy. The hippocampi were obtained from rats and subjected to western blot. Immunohistochem-istry was conducted to investigate the underlying mechanisms.Results: Rats received curcumin demonstrated improvement of recognition deficiency and epilepsy syndromes induced by KA. Western blot showed that KA stimulation increased the expression of IL-1β and NLRP3, which were reduced by curcumin treatment. Further investigations revealed that curcumin inhibited the activation of NLPR3/inflammasome in epilepsy and reduced neuronal loss in hippocampus.Conclusion: Curcumin inhibits KA-induced epileptic syndromes via suppression of NLRP3 in-flammasome activation; therefore, offers a potential therapy for epilepsy.

In Vivo Mapping and Quantification of Creatine Using Chemical Exchange Saturation Transfer Imaging in Rat Models of Epileptic Seizure.

To evaluate signal changes in the hippocampus of epileptic seizure rat models, based on quantified creatine chemical exchange saturation transfer (CrCEST) signals. CEST data and 1H magnetic resonance spectroscopy (1H MRS) data were obtained for the two imaging groups: control (CTRL) and epileptic seizure-induced (ES; via kainic acid [KA] injection) groups. CrCEST signals in the hippocampal regions were quantitatively evaluated; correlations between CrCEST signals and phosphocreatine (PCr) and total creatine (tCr; PCr + Cr) concentrations, derived from the analysis of 1H MRS data, were investigated as a function of time changes (before KA injection, 3 and 5h after KA injection). Measured CrCEST signals were exhibited significant differences between before and after KA injection in the ES group. At each time point, CrCEST signals showed significant correlations with PCr concentration (all |r| > 0.59; all P < 0.05); no significant correlations were found between CrCEST signals and tCr concentrations (all |r| < 0.22; all P > 0.05). CrCEST can adequately detect changes in the concentration of Cr as a result of energy metabolism, and may serve as a potentially useful tool for diagnosis and assessment of prognosis in epilepsy.

&lt;i&gt;Astragalus polysaccharide&lt;/i&gt; relieves reproductive toxicity in phenobarbital-treated epileptic rats

Purpose: To investigate the underlying mechanisms by which Astragalus polysaccharide (APS) relieves the reproductive toxicity induced by phenobarbital (PB) treatment in epileptic rats.Methods: Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay kits were used to quantify cell apoptosis in an epileptic rat model. The weight of sex organs and levels of three reproductive hormones, viz, follicle stimulating hormone (FSH), luteinizing hormone (LH) and testosterone, were measured in order to evaluate the effect of APS administration on reproductive ability. Concentration, motility, morphology as well as fertilization rate of sperms were analyzed as well.Results: Increase in sex organ weight and decrease in apoptosis were both associated with oral APS treatment. In APS-treated group, FSH, LH, and testosterone levels were raised while concentration, motility and normal morphology of sperm also increased. This was consistent with the observed increase in fertilization rate. In addition, hematoxylin and eosin (HE) staining of the testis was performed in the epileptic rat model showed that the size of cell lumen increased in APS-treated group. All APSassociated phenotypes occurred in a concentration-dependent manner.Conclusion: These data suggest that APS lowers reproductive toxicity in PB-treated epileptic rats by regulating the reproductive hormones, FSH, LH and testosterone, and also by altering the concentration, motility, and morphology of sperm. Thus, APS has a potential treatment for minimizing the side effects of antiepileptic drugs.Keywords: Astragalus polysaccharide, Reproductive toxicity, Phenobarbital, Epileptic rats

Protective effect of Fructus corni polysaccharide on hippocampal tissues and its relevant mechanism in epileptic rats induced by lithium chloride‑pilocarpine

The aim of the present study was to investigate the potential effect of Fructus corni polysaccharide (PFC) on the hippocampus tissues in epileptic rats induced by lithium chloride-pilocarpine, and to explore the underlying mechanism. The epileptic rat models were established using lithium chloride-pilocarpine treatment. According to the dosage of PFC, the rat models were divided into three groups: The low-dose (100 mg/kg/day), middle-dose (200 mg/kg/day) and high-dose (300 mg/kg/day) groups. The intervention for rat models lasted for 24 days. Subsequently, the production levels of reactive oxygen species (ROS) and malondialdehyde (MDA), the activity of superoxide dismutase (SOD), the mitochondrial membrane potential and the expressions of mitogen-activated protein kinase [P-38, Janus kinase (JNK) and extracellular signal-regulated kinase 1/2], cytochrome-C and caspase-3 in hippocampal tissues were detected. In addition, the structure of the CA-1 region of the hippocampus was also observed. Compared with the control group, the production levels of ROS were increased and the mitochondrial membrane potential was decreased in the hippocampus tissues of rats in the model group. In addition, in the model group, it was observed that MDA content was increased, SOD activity was decreased, and the expressions of phosphorylated (p)-p38, p-JNK, cytochrome-c and caspase-3 were increased, compared with the control group. Furthermore, those abnormal variations of the indicators were reversed by the intervention of PFC. These findings suggest that PFC can ameliorate the secondary damage to the hippocampi of epileptic rats, and that the anti-oxidation and -apoptosis effects of PFC may be associated with the mechanism that provides a protective effect for hippocampal tissues.

Development and Characterization of a Sucrose Microneedle Neural Electrode Delivery System

AbstractStable brain–machine interfaces present extraordinary therapeutic and scientific promise. However, the electrode–tissue interface is susceptible to instability and damage during long‐term implantation. Soft, flexible electrodes demonstrate improved longevity, but pose a new challenge with regard to simple and accurate surgical implantation. A high aspect ratio water‐soluble microneedle is developed based on sucrose which permits straightforward surgical implantation of soft, flexible microelectrodes. Here, a description of the microneedle manufacturing process is presented, along with in vitro and in vivo safety and efficacy assessments. Successful fabrication requires control of the glass transition temperature of aqueous sucrose solutions. The insertion force of 5 different microneedle electrode vehicles is studied in agarose brain phantoms, with the sucrose microneedle eliciting the lowest insertion force and strain energy transfer. Short‐ and long‐term assessments of the pathological response to sucrose microneedle implantations in the brain suggest minimal tissue reactions, comparable to those observed following stainless‐steel hypodermic needle punctures. Finally, microelectrodes fabricated from graphene, carbon nanotubes, or platinum are embedded in sucrose microneedles and implanted into an epileptic rat model for 22 d. All electrodes are functional throughout the implantation period, with the graphene electrode exhibiting the largest seizure signal‐to‐noise ratio and only modest changes in impedance.

Whole-transcriptome screening reveals the regulatory targets and functions of long non-coding RNA H19 in epileptic rats

Understanding the molecular mechanisms mediating epileptogenesis may lead to the development of preventative therapies against epilepsy. Our previous study demonstrated that the long non-coding RNA H19 contributes to epileptogenesis by aggravating status epilepticus-induced neuronal loss, glial cell activation, mossy fiber sprouting, and cognitive impairments in epileptic rats. However, the systematic functions and downstream targets of H19 associated with epileptogenesis are still unknown. In the present study, high-throughput microarray analysis was used to explore the influence of H19 on gene expression in an epileptic rat model. A large number of genes were differentially expressed at the transcriptional level when H19 was overexpressed or knocked down. Series test of cluster analysis further distinguished genes associated with H19. Function and pathway analyses demonstrated that H19 has diverse functions related to epileptogenesis, including demyelination, immune and inflammatory responses, cell apoptosis, and activation of MAPK. This study implicates H19 in a broad spectrum of epileptogenic processes, thereby providing a range of targets for further mechanistic investigations.

Nitrobenzylthioinosine mimics adenosine to attenuate the epileptiform discharge of hippocampal neurons from epileptic rats.

Nitrobenzylthioinosine (NBTI), a specific inhibitor of type 1 equilibrative nucleoside transporter, could regulate the extracellular adenosine concentration and have protective roles in seizures. However, the protection mechanism of NBTI in seizures remains poorly understood. Here, the expression pattern and subcellular distribution of adenosine A1 receptor were detected by Western blot analysis and double-labeling immunofluorescence staining in Lithium Chloride-Pilocarpine induced epileptic rat model. At 24 h after pilocarpine induced rat seizures, hippocampal slices were prepared and the evoked excitatory postsynaptic currents (eEPSCs) amplitude of pyramidal neurons in hippocampus CA1 region was recorded using whole-cell patch clamp. In vivo, compared to control group, Western blotting analysis showed that the expression of adenosine A1 receptor protein was increased at 24 h and 72 h after seizure, didn't change at 0 min and 1 w, and decreased at 2 w. Double-label immunofluorescence revealed that adenosine A1 receptor was mainly expressed in the membrane and cytoplasm of neurons. In Vitro, adenosine decreased the eEPSCs amplitude of pyramidal neurons in hippocampus CA1 region, NBTI also had the same effect. Meantime, NBTI could further inhibit eEPSCs amplitude on the basis of lower concentration adenosine (50μM), and adenosine A1 receptor inhibitor DPCPX partially reversed this effect. Taken together, we confirmed that the expression of adenosine A1 receptor protein was increased in the early seizures and decreased in the late seizures. At the same time, NBTI mimics adenosine to attenuate the epileptiform discharge through adenosine A1 receptor, which might provide a novel therapeutic approach toward the control of epilepsy.

Neuroimmunomodulatory Role of Spinacea Oleracea on Blastogenic Activity in Penicillin Induced Experimental Epileptic Rat Model

Neuroimmunomodulatory Role of Spinacea Oleracea on Blastogenic Activity in Penicillin Induced Experimental Epileptic Rat Model

The expression of calcium sensing receptor(CaSR) and MAPK pathway changes in myocardial cells of epilepsy rats

To investigate the changes of the myocardial cells in chronic epileptic rat model and to observe the expression of calcium sensing receptor(CaSR) and mitogen-activated proteinkinase(MAPK)pathway changes in epilepsy rats. The chronic epileptic rat model was induced bypentetrazole (PTZ). Adult male Wistar rats were divided into 5 groups randomly, and there were 12 rats in each group. The rats in model group were treated with a sub-convulsivedose of PTZ (35 mg/kg) by intraperitoneal injection for 28 d. After stopping a week, the same dose of PTZ test was conducted. The control group was treated with isovolumetric saline instead of PTZ by intraperitoneal injection. According to Racine behavior grading standards the rat emerged two levels above epileptic seizure 5 consecutive times, which was considered the chronic epilepsy model successful ignition. The intervention factors included spermine(calcium-sensing receptor agonist, 3 μmol/L) and Chalhex231(calcium-sensing receptor inhibitor, 2 μmol/L). The serum creatine kinase (CK) and creatine kinase isoenzyme(CK-MB)were detected. The cardiac functions, morphological changes of rat myocardial tissue, myocardial cell ultrastructure, myocardial cell calcium sensing receptor and extracellular regulated protein kinase (ERK), p-ERK, p-JNK expression were carried out. Compared with normal control group, CK, CK-MB inPTZ group were increased obviously. The cardiac compliance and left ventricular function were decreased, E/A<1 by echocardiography. The myocardial ultrastructure showed serious injury. The expressions of CaSR and p-JNK were increased, but the expression of p-ERKwas decreased. Spermine could promote the expressions of CaSR and p-JNK, and decrease the expression of p-ERK in epilepsy; however, the role of Chalhex231 wasopposite. The level of CaSR expression increased in chronic epileptic rat model. CaSR activated the expressions of MAPK of the myocardial cells,andthen influenced the cardiac myocyte apoptosis.

Down-regulation of adenylate kinase 5 in temporal lobe epilepsy patients and rat model

Adenylate kinase 5 (AK5) is one member of the AK family and plays a critical role in maintaining cellular homeostasis. Different from the other AKs, AK5 is almost exclusively expressed in the brain. However, its exact biological functions remain unclear. The aim of the present study is to explore the expression pattern of AK5 in patients with refractory epilepsy and in a chronic pilocarpine-induced epileptic rat model. Using Western blot, immunofluorescence and immunoprecipitation analysis, we found that AK5 protein was mainly expressed in neurons, demonstrated by colocalization with the dendritic marker, MAP2, which were similar to the corresponding controls. However, the expression of AK5 decreased remarkably in epileptic patients and experimental rats. Furthermore, immunoprecipitation analysis showed that the interaction of AK5 with copine VI (CPNE6, a brain specific protein) increased in epileptic patients and rat models. Our results are the first to indicate that the expression of AK5 in epileptic brain tissue may play important roles in epilepsy, especially refractory epilepsy.

A Bidirectional Neural Interface Circuit With Active Stimulation Artifact Cancellation and Cross-Channel Common-Mode Noise Suppression

This work presents a bidirectional neural interface circuit that enables simultaneous recording and stimulation with a stimulation artifact cancellation circuit. The system employs a common average referencing (CAR) front-end circuit to suppress cross-channel environmental noise to further facilitate use in clinical environment. This paper also introduces a new range-adapting (RA) SAR ADC to lower the system power consumption. A prototype is fabricated in $0.18\;\mu {\rm{m}}$ CMOS and characterized and tested in vivo in an epileptic rat model. The prototype attenuates stimulation artifacts by up to 42 dB and suppresses cross-channel noise by up to 39.8 dB. The measured power consumption per channel is 330 nW, while the area per channel is 0.17 mm $^2$ .

The inhibition of transforming growth factor beta-activated kinase 1 contributed to neuroprotection via inflammatory reaction in pilocarpine-induced rats with epilepsy

Recently, more and more studies support that inflammation is involved in the pathogenesis of epilepsy. Although TGFβ signaling is involved in epileptogenesis, whether TGFβ-associated neuroinflammation is sufficient to regulate epilepsy remains unknown to date. Furthermore, tumor necrosis factor-α receptor-associated factor-6 (TRAF6), transforming growth factor beta-activated kinase 1 (TAK1), which are the key elements of TGFβ-associated inflammation, is still unclear in epilepsy. Therefore, the present study aimed to explore the role of TRAF6 and TAK1 in pilocarpine-induced epileptic rat model. Firstly, the gene levels and protein expression of TRAF6 and TAK1 were detected in different time points after pilocarpine-induced status epilepticus (SE). 5z-7-oxozeaenol treatment (TAK1 antagonist) was then performed; the changes in TRAF6, TAK1, phosphorylated-TAK1 (P-TAK1), interleukin-1β (IL-1β) levels, neuronal survival and apoptosis, and seizure activity were detected. Our results showed that expressions of TRAF6 were increased after SE, reached the peak in 7day, maintained at the high level to 30days, and the TAK1, P-TAK1 levels were increased after SE following time. After 5z-7-oxozeaenol treatment in epileptic rats, TRAF6–TAK1–P-TAK1 signaling protein expressions were reduced, inflammatory cytokine IL-1β expression was decreased, neuron survival index was improved, the neuron apoptosis index was decreased and seizure durations were alleviated. In conclusion, the expression of TRAF6 and TAK1 are related to the progression of epilepsy. TAK1 might be a potential intervention target for the treatment of epilepsy via neuroprotection.

Upregulated P2X3 Receptor Expression in Patients with Intractable Temporal Lobe Epilepsy and in a Rat Model of Epilepsy.

Purinergic P2X3 receptors (P2X3Rs) play extensive roles in nerve cells in the central nervous system, particularly in hyperexcitability and calcium (Ca(2+)) influx. However, the role of P2X3Rs in epilepsy has not been previously investigated. To determine the relationship between P2X3Rs and epilepsy, the expression and cellular location of P2X3Rs in patients with intractable temporal lobe epilepsy (TLE) and in a lithium chloride-pilocarpine-induced chronic rat model of epilepsy were assessed. Furthermore, the function of P2X3Rs was assessed in vitro. Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis were used to evaluate the expression levels of P2X3Rs in brain tissues from TLE patients and an epileptic rat model, whereas immunofluorescence labeling was applied to determine the distribution of target proteins. Whole-cell recording was subsequently performed to identify the influence of P2X3Rs on seizure-like discharges. P2X3Rs were located at the cell bodies and dendrites of neurons with significantly increased expression in the TLE patients and epileptic rat model. In vitro, P2X3R activation accelerated sustained repetitive firing, whereas P2X3R inhibition led to relatively low-frequency discharges. To the best of our knowledge, this is the first study provide evidence that upregulated P2X3R expression exists in both epileptic humans and rats and may aggravate the epileptic state in vitro. Thus, P2X3Rs may represent a novel therapeutic target for antiepileptic drugs.

Study on protective effect of ketogenic diet against hippocampal neurons of kainic acid-induced epileptic rats

Objective To investigate the protective effects of ketogenic diet on hippocampal neurons of kainic acid (KA)-induced epileptic rats. Methods A total of 40 healthy male specific pathogen free (SPF) Sprague-Dawley (SD) rats were randomly divided into 4 groups, with each group containing 10 rats. Epileptic rat models were formed by injection of KA through lateral ventricle with brain stereotactic instrument. According to Racine classification, epileptic seizures in rats above grade Ⅳ were defined successful. Then the rats were given different dietary treatment: Group C with normal saline and normal diet, Group K with normal saline and ketogenic diet, Group E with KA and normal diet, Group EK with KA and ketogenic diet. All rats were observed for 21 d, and were recorded each body weight. The epileptic seizure frequency and duration were observed at 12:00-15:00 daily. At the 21st day, all rats were put to death, and the brain hippocampus tissues were separated. Neuron injury of rat hippocampal CA3 region in Group E and EK was observed by HE staining. Normal neuron number of rat hippocampal CA3 region in Group E and EK was counted by Nissl staining. Results Group C and K had no epileptic seizures, and the neuron number in hippocampal CA3 region was normal. Rats in both Group E and EK had grade Ⅳ or Ⅴ seizures. The number of seizures in Group EK [(17.90 ± 4.12) times] after 21-day ketogenic diet was decreased significantly compared to Group E [(30.50 ± 4.40) times] after 21-day normal diet ( t = 6.606, P = 0.000). The seizure duration in Group EK [(212.70 ± 17.75) s] after 21-day ketogenic diet was shortened compared to Group E [(335.00 ± 14.21) s] after 21-day normal diet ( t = 17.011, P = 0.000). The normal neuron number in hippocampal CA3 region in Group EK (117.67 ± 7.51) was more than those in Group E (71.33 ± 6.11), with statistically significant difference ( t = 9.614, P = 0.000). Conclusions Ketogenic diet has protective effect on hippocampal neurons of kainic acid-induced epileptic rats. DOI: 10.3969/j.issn.1672-6731.2015.11.011

Increased expression of copine VI in patients with refractory epilepsy and a rat model

Copine VI (CPNE6) is a member of copines family, a calcium-dependent phospholipids-binding protein group found in many diverse eukaryotic organisms. Although earlier studies have shown that CPNE6 is almost exclusively expressed in brain, the exact biological functions remain unclear. The purpose of this study is to explore the relationship between epilepsy and CPNE6 expression. In present study, we investigated the expression pattern and distribution of CPNE6 in patients with refractory epilepsy and in a chronic pilocarpine-induced epileptic rat model by quantitative real-time PCR, Western blot and immunofluorescence. The results showed that the expression of CPNE6 increased remarkably in epileptic patients and in experimental epileptic rats. Double immunofluorescence labeling studies have revealed that CPNE6 protein is mainly expressed in neurons, demonstrated by co-localization with the dendritic marker, MAP2. Our results are the first to indicate that the abnormal expression of the CPNE6 in epileptic brain tissue may play an important role in epilepsy, especially refractory epilepsy.

Neurofibromin Regulates Seizure Attacks in the Rat Pilocarpine-Induced Model of Epilepsy.

Studies have shown that neurofibromin (NF1) restricts GABA release at inhibitory synapses and regulates dendritic spine formation, which may play an important role in temporal lobe epilepsy (TLE). NF1 expression was detected by double-label immunofluorescence, immunohistochemistry, and western blot analysis in the brains of pilocarpine-induced epilepsy model rats at 6h, 24h, 72h, 7days, 14days, 30days, and 60days after kindling. NF1 was localized primarily in the nucleus and cytoplasm of neurons. NF1 protein levels significantly increased in the chronic phase (from 7days until 60days) in this epileptic rat model. After NF1 expression was knocked down by specific siRNA, the effects of kindling with pilocarpine were evaluated on the 7th day after kindling. The onset latencies of pilocarpine-induced seizures were elevated, and the seizure frequency and duration were reduced in these rats. Our study demonstrates that NF1 promoted seizure attacks in rats with pilocarpine-induced epilepsy.

Study on the changes and significance of serum NSE, S-100B and GFAP in immature rat model of epileptic seizure

Objective To observe the dynamic changes of neuron-specific enolase (NSE), S-100B protein (S-100B) and glial fibrillary acidic protein (GFAP) in the serum of immature epileptic rat model, so as to explore the significance of these biochemical indexes on the damage of immature brain after epileptic seizures. Methods The immature epileptic rat model was established by inducing flurothyl to 5-day-old specific pathogen free (SPF) Sprague-Dawley (SD) rats. The experimental animals were randomly divided into 2 groups: control group (N = 8) and seizure group (N = 64). Furthermore, the latter was subdivided into single seizure group (N = 32) and repeated seizures group (N = 32). Double antibody sandwich enzyme-linked immunosorbent assay (ELISA) was used to detect the changes of serum NSE, S-100B and GFAP in control group, single seizure group and repeated seizures group, on the 1st, 2nd, 7th and 15th days of the seizure onset. Results Compared with control group, the concentrations of serum NSE and S-100B in single seizure group increased significantly on the 1st day of onset ( P = 0.000, for all), which respectively rose up to (8.57 ± 0.56) μg/L and (0.45 ± 0.06) μg/L, and then declined gradually to normal ( P > 0.05, for all), while no obvious changes of GFAP was found. Compared with control group, the concentrations of serum NSE and S-100B in repeated seizures group reached the peak on the 1st day of onset [(9.33 ± 0.61) μg/L and (0.78 ± 0.10) μg/L; P = 0.000, for all], and then declined gradually to normal on the 7th and 15th days ( P > 0.05, for all). Compared with control group, the concentration of serum GFAP in repeated seizures group increased significantly on the 1st day of onset [(0.44 ± 0.05) μg/L, P = 0.004], reached the peak on the 7th day [(0.63 ± 0.08) μ g/L, P = 0.000], then declined gradually, but was still significantly higher than that in control group on the 15th day [(0.40 ± 0.05) μg/L, P = 0.018]. Conclusions NSE and S-100B are highly sensitive biochemical markers of brain damage caused by single convulsive seizure. Repeated convulsive seizures could aggravate brain damage. GFAP is not a sensitive predictive indicator on brain damage caused by single convulsive seizure. DOI: 10.3969/j.issn.1672-6731.2015.11.010

Cognitive impairment and spontaneous epilepsy in rats with malformations of cortical development

PurposeTo examine the cognition, spontaneous epilepsy, and electroencephalography (EEG) characteristics of rats with malformations of cortical development (MCD) and their use as an animal model for investigating the pathogenesis of intractable epilepsy and screening novel antiepileptic drugs. MethodsAn epileptic rat model of MCD was established with the F1 generation of pregnant rats after X-irradiation with 175 cGy (Group L), 195 cGy (Group M), or 215 cGy (Group H). Long-term video-EEG monitoring was used to record the seizures in the rats with MCD. Cognition was assessed with the Morris water maze. The EEGs were recorded and analyzed in the frontal and parietal lobes and hippocampi of adult rats. Finally, the brain tissues were processed for Nissl staining. ResultsThe model groups exhibited markedly prolonged escape latencies and distinct decrements in the percent distance traveled in the target quadrant and platform-crossing frequency. These findings were dose-dependent. Frequent interictal epileptiform discharges were observed in the frontal and parietal lobes and hippocampi of adult rats, and their incidences were markedly higher in the model groups compared with that in the normal controls, with Group M having the highest incidence. Spontaneous seizures were observed in the model groups (mean incidence, 46.7%). The daily mean frequency of seizures and the incidence of spontaneous seizures were highest in Group M. Nissl staining revealed a dose-dependent pattern of hippocampal abnormalities, cortical and subcortical nodular heterotopia, and callosal agenesis in the model groups. ConclusionThe 195 cGy dose was most appropriate for establishing an epileptic model of MCD with X-irradiation.

Enniatin B mycotoxin is excreted as such to rat urine

Copine VI (CPNE6) is a member of copines family, a calcium-dependent phospholipids-binding protein group found in many diverse eukaryotic organisms. Although earlier studies have shown that CPNE6 is almost exclusively expressed in brain, the exact biological functions remain unclear. The purpose of this study is to explore the relationship between epilepsy and CPNE6 expression. In present study, we investigated the expression pattern and distribution of CPNE6 in patients with refractory epilepsy and in a chronic pilocarpine-induced epileptic rat model by quantitative real-time PCR, Western blot and immunofluorescence. The results showed that the expression of CPNE6 increased remarkably in epileptic patients and in experimental epileptic rats. Double immunofluorescence labeling studies have revealed that CPNE6 protein is mainly expressed in neurons, demonstrated by co-localization with the dendritic marker, MAP2. Our results are the first to indicate that the abnormal expression of the CPNE6 in epileptic brain tissue may play an important role in epilepsy, especially refractory epilepsy.