Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036572 (seizures)
 80,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The high fat, low carbohydrate, low protein ketogenic diet (KD) has been used to control refractory epilepsy in children since 1920, although its mechanism of action is unknown. Previous animal studies have shown that the KD can increase acute seizure threshold, but the effect of the KD on the process of epileptogenesis has not been studied. We tested the effect of an experimental KD on epileptogenesis in adult rats using the kainic acid (KA) model. P54 rats underwent KA-induced status epilepticus, followed by assignment to a control diet or a KD consisting of (by weight), 14% protein, 70% fat and no carbohydrate. KD-fed animals tolerated the diet and maintained ketosis. KD-fed rats had significantly fewer and briefer spontaneous recurrent seizures and less supragranular mossy fiber sprouting, although the degree of hippocampal pyramidal cell damage was similar in both groups. These results provide the first evidence that the KD retards epileptogenesis in an experimental model.
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PMID:Ketogenic diet reduces spontaneous seizures and mossy fiber sprouting in the kainic acid model. 1038 Sep 73

The electrophysiological effects of the high-fat, low-carbohydrate ketogenic diet (KD) were assessed in normal and epileptic [kainic-acid(KA)-treated] adult rats using hippocampal slices. In the first set of experiments, normal rats were fed the KD or a standard control diet for 6-8 weeks (beginning on postnatal day 56, P56), after which they were sacrificed for hippocampal slices. All rats on the KD became ketotic. The baseline effects of the KD were determined by comparing extracellular measures of synaptic transmission and responses to evoked stimulation, and hippocampal excitability was tested in Mg(2+)-free medium. There were no differences in EPSP slope, input/output relationship, responses to evoked stimulation or Mg(2+)-free burst frequency between slices from control and KD-fed rats. In another set of experiments, rats were made epileptic by intraperitoneal injection of kainic acid (KA) on P54, which caused status epilepticus followed by the development of spontaneous recurrent seizures (SRS) over the next few weeks. Two days after KA-induced status, rats were divided into a control-fed group and a KD-fed group. Animals on the KD had significantly fewer SRS over the ensuing 8 weeks. In hippocampal slices from KA-treated, KD-fed rats, there were fewer evoked CA1 population spikes than from slices of control-fed rats. These results suggest that the KD does not alter baseline electrophysiological parameters in normal rats. In rats made chronically epileptic by administration of KA, KD treatment was associated with fewer spontaneous seizures and reduced CA1 excitability in vitro. Therefore, at least part of the KD mechanism of action may involve long-term changes in network excitability.
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PMID:Electrophysiological observations in hippocampal slices from rats treated with the ketogenic diet. 1057 63

For the purpose of investigating the role of physical exercise in developmental seizure-induced cognitive deficit, hippocampal mossy fiber sprouting and related gene expression, a seizure was induced by penicillin every other day in Sprague-Dawley rats from postnatal day 24 (P24). The authors assigned ten rats each randomly into the control group (CONT1), the control plus exercise group (CONT2), the seizure group (EXP1) and the seizure plus exercise group (EXP2). Morris water maze test was used respectively during P39-P45 and P61-P66. Treadmill exercise was performed daily by CONT2 and EXP2 rats during P49-P54. On P66, mossy fiber sprouting and gene expression in hippocampus were assessed by Timm staining and real-time RT-PCR. EXP2 rats performed better than EXP1 rats in the second water maze navigation test. In the entire two spatial probe tests, both EXP1 and EXP2 rats performed worse than the two control rats. Physical exercise remarkably reduced the aberrant mossy fiber sprouting in the supragranular region of dentate gyrus and CA3 subfield of hippocampus. Both EXP1 and EXP2 rats had a higher amount of glutamate receptor 1 (GluR1) and lower amount of the ratio of GluR2/GluR1 in hippocampus when compared with CONT rats. In addition, there was long-term enhancement of both gamma-aminobutyric acid receptor A-alpha3 (GABA-Aalpha3) and cholecystokinin (CCK) of EXP2 rats compared with the other three groups. These results showed that physical exercise improved learning capacity by modulating hippocampal regenerative sprouting and related gene expression in a developmental rat model of penicillin-induced recurrent epilepticus.
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PMID:Physical exercise improves learning by modulating hippocampal mossy fiber sprouting and related gene expression in a developmental rat model of penicillin-induced recurrent epilepticus. 1966 89

Neuregulin 1 (NRG1)-induced activation of ErbB4 in parvalbumin (PV) inhibitory interneurons is reported to serve as a critical endogenous negative-feedback mechanism to repress brain epileptogenesis. Here, we investigated the seizure susceptibility and the role of NRG1-ErbB4 signaling in PV interneurons in the suppression of epileptic seizures for rats subject to early life hypoxia. Neonatal postnatal day 5 (P5) rats were exposed to intermittent hypoxia (IH) or control (CON) room air for 10 days. In the prefrontal cortex (PFC) of P54 rats, we determined the impact of neonatal IH exposures on the expression of PV, NRG1, ErbB4, and phosphorylated ErbB4 (p-ErbB4) during the seizure induction. Seizure susceptibility tests with the common convulsant agent pentylenetetrazole (PEN) at P54 revealed that rats subject to neonatal hypoxia exposure developed faster and more serious epileptic seizures. Neonatal IH exposures (1) decreased the number of PV cells in the PFC of P54 rats; (2) interrupted the expression of NRG1 gene; and (3) altered the activity of NRG1 on PV interneurons in the PFC after the seizure induction. Intracerebroventricular delivery of exogenous NRG1 before seizure induction by PEN significantly reduced the seizure susceptibility for neonatal IH-exposed rats. The ErbB4 inhibitor AG1478 inhibited the exogenous NRG1's effects on seizure susceptibility. Environmental enrichment (EE) rescued the abovementioned pathophysiological alterations and significantly attenuated the epileptic seizures after the seizure induction for neonatal IH-exposed rats. Our study indicated early life hypoxia exposure might increase the seizure susceptibility for rats and contribute to pathophysiological dysfunction of NRG1-ErbB4 signaling in PV interneurons in the suppression of epileptic seizures. EE might attenuate the increased seizure susceptibility for neonatal IH-exposed rats through rescuing pathophysiological alterations of NRG1-ErbB4 signaling in PV interneurons.
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PMID:Increased Seizure Susceptibility for Rats Subject to Early Life Hypoxia Might Be Associated with Brain Dysfunction of NRG1-ErbB4 Signaling in Parvalbumin Interneurons. 3287 Apr 92