Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0014547 (focal epilepsy)
 1,627 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The NMDA receptor is one of the ionotropic glutamate receptors essential for excitatory neurotransmission. The NMDAR1 subunit is inactivated by direct interaction with calmodulin. The protein levels of calmodulin, NMDAR1 and their complex were quantified in tissue resected from epileptogenic and non-epileptogenic cortical areas as determined by chronic subdural electrode recordings from three patients (aged 6, 14 and 18 years) with focal epilepsy associated with cortical dysplasia. In all patients, the co-assembly of calmodulin and NMDAR1 was decreased in epileptogenic dysplastic cortex compared with normal appearing non-epileptogenic cortex, while there was no significant difference in the total protein levels of calmodulin or NMDAR1 between the two EEG groups. These results suggest that decreased calmodulin-NMDAR1 co-assembly is a cellular mechanism that contributes to hyperexcitability in dysplastic cortical neurons and in focal seizure onsets.
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PMID:Decreased calmodulin-NR1 co-assembly as a mechanism for focal epilepsy in cortical dysplasia. 1038 Sep 90

Since a disturbed balance between excitatory and inhibitory amino acid receptors is suggested to be an important condition for epileptogenic cortical activity, the present study has focused on the analysis of the densities of (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA), N-methyl-D-aspartate, kainate and GABA subtype A receptors in neocortical tissue surgically removed from patients with focal epilepsy. The mean densities (collapsed over cortical layers I-VI) and the laminar distribution patterns of [3H]AMPA, [3H]MK-801, [3H]kainate and [3H]muscimol binding to AMPA, N-methyl-D-aspartate, kainate and GABAA receptors were determined with quantitative receptor autoradiography in the neocortex of patients with focal epilepsy and controls. The tissue probes used in the present study were functionally characterized by parallel electrophysiological investigations. From that, the different probes could be subdivided into a spontaneously spiking and a non-spontaneously spiking group. The mean density of [3H]AMPA binding sites was significantly increased (+37%) in the group of epileptic brains (n = 10) compared with controls (n = 10), but the mean densities of [3H]MK-801, [3H]kainate and [3H]muscimol binding sites were not significantly altered (-8%, +/-0% and -7%, respectively). The relation between the densities of all four binding sites were simultaneously displayed as polar plots in each single brain ("receptor fingerprints"). The consistent up-regulation of [3H]AMPA binding sites in all epileptic brains was found to be associated with a down-regulation of the N-methyl-D-aspartate receptor in four of the five non-spontaneously spiking cases, and an associated up-regulation of the N-methyl-D-aspartate receptor was seen in all spontaneously spiking cases. Finally, the laminar distribution of binding site densities was analysed, since the mean densities collapsed over all neocortical layers may obscure layer-specific alterations. Layer- and receptor- specific up- or down-regulations were found in epileptic tissue compared with controls. Moreover, the laminar distribution pattern of current sinks associated with epileptiform potentials in a spontaneously spiking cortical slice was found to be co-localized with local maxima of AMPA receptor densities. The present analysis of four ionotropic glutamate and GABA receptor subtypes demonstrates a consistent and significant up-regulation of [3H]AMPA binding sites in all cases of human focal epilepsy, which co-localizes with the occurrence of sinks in current-source-density analysis. The receptor fingerprint analysis suggests a subdivision of focal epilepsy into two subtypes on the basis of neurochemical/functional correlations: (i) a spontaneously spiking subtype with increased N-methyl-D-aspartate receptor density, and (ii) a non-spontaneously spiking subtype with decreased N-methyl-D-aspartate receptor density.
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PMID:Ionotropic glutamate and GABA receptors in human epileptic neocortical tissue: quantitative in vitro receptor autoradiography. 1062 47

Introduction: Perampanel is an antiepileptic drug approved in the USA and Europe as monotherapy and adjunctive therapy for focal onset seizures and as adjunctive therapy for generalized tonic-clonic seizures. Areas covered: This an overview of animal data, pharmacokinetics, and clinical data published on Perampanel indexed in PubMed. Expert opinion: Pharmacological studies suggest that perampanel acts via noncompetitive antagonism of the ionotropic AMPA receptor of glutamate. The efficacy of perampanel has been shown in animal models of epilepsy and Phase II/III clinical trials. Efficacy and safety have been evaluated in the phase III trials of adjunctive treatment of focal epilepsy with median focal onset seizure reduction rates of 23% for 4 mg/d, 26-31% for 8 mg/day, and 18-35% for 12 mg/day. Fifty percent responder rates were 29% for 4 mg/day, 33-38% for 8 mg/day, and 34-36% for 12 mg/day. A pivotal Phase III trial in generalized onset tonic-clonic seizures showed a median seizure reduction by 76.5% (8 mg) versus 38.4% placebo and 50% seizure responder rate of 64.2% versus 30.9% placebo. Perampanel showed good safety and tolerability profile across 2-12 mg doses. Perampanel as a broad-spectrum antiepileptic drug has a potential to be an alternative treatment of multiple types of epileptic seizures.
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PMID:Perampanel as monotherapy and adjunctive therapy for focal onset seizures, focal to bilateral tonic-clonic seizures and as adjunctive therapy of generalized onset tonic-clonic seizures. 3056 Jul 3