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Naffaa MM, Al-Ewaidat OA. Ligand modulation of KCNQ-encoded (K V7) potassium channels in the heart and nervous system. Eur J Pharmacol 2021; 906:174278. [PMID: 34174270 DOI: 10.1016/j.ejphar.2021.174278] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/06/2021] [Accepted: 06/18/2021] [Indexed: 10/21/2022]
Abstract
KCNQ-encoded (KV7) potassium channels are diversely distributed in the human tissues, associated with many physiological processes and pathophysiological conditions. These channels are increasingly used as drug targets for treating diseases. More selective and potent molecules on various types of the KV7 channels are desirable for appropriate therapies. The recent knowledge of the structure and function of human KCNQ-encoded channels makes it more feasible to achieve these goals. This review discusses the role and mechanism of action of many molecules in modulating the function of the KCNQ-encoded potassium channels in the heart and nervous system. The effects of these compounds on KV7 channels help to understand their involvement in many diseases, and to search for more selective and potent ligands to be used in the treatment of many disorders such as various types of cardiac arrhythmias, epilepsy, and pain.
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Affiliation(s)
- Moawiah M Naffaa
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, 27710, USA; Department of Psychology and Neuroscience, Duke University, Durham, NC 27708, USA.
| | - Ola A Al-Ewaidat
- Faculty of Medicine, The University of Jordan, Amman, 11942, Jordan
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An overview of structurally diversified anticonvulsant agents. ACTA PHARMACEUTICA (ZAGREB, CROATIA) 2019; 69:321-344. [PMID: 31259739 DOI: 10.2478/acph-2019-0023] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/15/2018] [Indexed: 01/19/2023]
Abstract
There are several limited approaches to treat epilepsy in hospitals, for example, using medicines, surgery, electrical stimulation and dietary interventions. Despite the availability of all these new and old approaches, seizure is particularly difficult to manage. The quest for new antiepileptic molecules with more specificity and less CNS toxicity continues for medicinal chemists until a new and ideal drug arrives. This review covers new antiseizure molecules of different chemical classes, the exact mode of action of which is still unidentified. Newer agents include sulfonamides, thiadiazoles, semi- and thiosemicarbazones, pyrrolidine-2,5-diones, imidazoles, benzothiazoles and amino acid deriva tives. These new chemical entities can be useful for the design and development of forthcoming antiseizure agents.
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De Iuliis V, Gelormini R, Flacco M, Moriello G, Caruso M, Barone E, Golato M, Toniato E, Conti P, Martinotti S. Comparison of Serum Total Valproic Acid Levels and %CDT Values in Chronic Alcohol Addictive Patients in an Italian Clinic: A Retrospective Study. Drugs Real World Outcomes 2016; 3:7-12. [PMID: 27747801 PMCID: PMC4819473 DOI: 10.1007/s40801-015-0053-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Background Valproate is a broad-spectrum anticonvulsant that is effective in the treatment of tonic-clonic, myoclonic and absence seizures as well as in partial seizures as a second-line drug. It has been widely demonstrated in the literature that the effect of valproate on type-A γ-aminobutyric acid (GABA-A) receptors may reduce relapse to ethanol abuse. This retrospective study evaluated a 3-year period in which 42 patients from the Department of Alcoholism and Substance Abuse (DASA) were treated with valproate. Objectives We compared different serum total valproic acid (VPA) concentrations, and the effectiveness of this drug in maintaining alcohol abstinence was evaluated by percentage of carbohydrate deficient transferrin (%CDT) values. Method CDT is a biochemical marker used for identifying regular high alcohol consumption and monitoring abstinence in outpatients during treatment. Serum concentrations of valproate were divided into four groups: <10, 10–30, 31–50, and >50 µg/mL. Results This study shows that a mean serum total VPA concentration >30 µg/mL is more effective in maintaining alcohol abstinence than a lower one (p < 0.05). In this study, mean serum total VPA concentrations between 31 and 50 µg/mL showed the same effectiveness as higher ones (>50 µg/mL); in fact, there was no significant difference in mean %CDT values between these two groups (p > 0.05). After at least 12 months’ treatment with valproate, mean platelet counts increased by 12 × 103/μL compared with baseline (254 ± 63 vs 242 × 103/μL, p > 0.05, respectively) in patients with mean serum total VPA levels <10 μg/mL; increased by 8 × 103/μL from baseline (253 ± 59 vs 245 × 103/μL, p > 0.05, respectively) in patients with levels between 10 and 30 μg/mL; decreased by 2 × 103/μL from baseline (265 ± 63 vs 267 × 103/μL, p > 0.05, respectively) in patients with levels between 31 and 50 μg/mL, and decreased by 48 × 103/μL from baseline (215 ± 56 vs 263 × 103/μL, p < 0.05, respectively) in patients with levels >50 μg/mL. Conclusion A mean serum total concentration lower than the currently accepted therapeutic level (50–100 µg/mL) may have the same effectiveness in maintaining alcohol abstinence with a lower risk of presenting side effects.
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Affiliation(s)
- Vincenzo De Iuliis
- Unit of Clinical Pathology, SS Annunziata University Hospital, ASL Lanciano-Vasto-Chieti, Via dei Vestini 31, Chieti, Italy
- Department of Medical, Oral and Biotechnologic Sciences, Via dei Vestini 31, Chieti, Italy
| | - Raimondo Gelormini
- Unit of Clinical Pathology, SS Annunziata University Hospital, ASL Lanciano-Vasto-Chieti, Via dei Vestini 31, Chieti, Italy
| | - Mariarosaria Flacco
- Unit of Clinical Pathology, SS Annunziata University Hospital, ASL Lanciano-Vasto-Chieti, Via dei Vestini 31, Chieti, Italy
| | - Giuseppe Moriello
- Unit of Clinical Pathology, SS Annunziata University Hospital, ASL Lanciano-Vasto-Chieti, Via dei Vestini 31, Chieti, Italy
- Department of Medical, Oral and Biotechnologic Sciences, Via dei Vestini 31, Chieti, Italy
| | - Marika Caruso
- Unit of Clinical Pathology, SS Annunziata University Hospital, ASL Lanciano-Vasto-Chieti, Via dei Vestini 31, Chieti, Italy
- Department of Medical, Oral and Biotechnologic Sciences, Via dei Vestini 31, Chieti, Italy
| | - Eugenia Barone
- Unit of Clinical Pathology, SS Annunziata University Hospital, ASL Lanciano-Vasto-Chieti, Via dei Vestini 31, Chieti, Italy
- Department of Medical, Oral and Biotechnologic Sciences, Via dei Vestini 31, Chieti, Italy
| | - Maria Golato
- Unit of Clinical Pathology, SS Annunziata University Hospital, ASL Lanciano-Vasto-Chieti, Via dei Vestini 31, Chieti, Italy
| | - Elena Toniato
- Department of Medical, Oral and Biotechnologic Sciences, Via dei Vestini 31, Chieti, Italy
| | - Pio Conti
- Immunology Division, Postgraduate Medical School, University of Chieti, Viale Unità d’Italia 73, Chieti, Italy
| | - Stefano Martinotti
- Department of Medical, Oral and Biotechnologic Sciences, Via dei Vestini 31, Chieti, Italy
- Unit of Clinical Molecular Biology and Predictive Medicine, SS Annunziata University Hospital, University of Chieti, ASL Lanciano-Vasto-Chieti, Chieti, Italy
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Lasoń W, Chlebicka M, Rejdak K. Research advances in basic mechanisms of seizures and antiepileptic drug action. Pharmacol Rep 2013; 65:787-801. [DOI: 10.1016/s1734-1140(13)71060-0] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 03/11/2013] [Indexed: 10/25/2022]
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Pastore V, Sabatier L, Enrique A, Marder M, Bruno-Blanch LE. Synthesis and anticonvulsant activity of bioisosteres of trimethadione, N-derivative-1,2,3-oxathiazolidine-4-one-2,2-dioxides from α-hydroxyamides. Bioorg Med Chem 2013; 21:841-6. [PMID: 23321016 DOI: 10.1016/j.bmc.2012.12.033] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 12/13/2012] [Accepted: 12/22/2012] [Indexed: 01/17/2023]
Abstract
The synthesis and anticonvulsant activity of novel heterocycles N-derivative-1,2,3-oxathiazolidine-4-one-2,2-dioxides, bioisosteres of trimethadione (TMD, oxazolidine-2,4-dione) and phenytoin (PHE), are described. TMD is an anticonvulsant drug widely used against absences seizures in the early 80's and PHE is an antiepileptic drug with a wide spectrum activity. The intermediates of synthesis of N-derivative-1,2,3-oxathiazolidine-4-one-2,2-dioxides, α-hydroxyamides, were obtained using microwave assisted synthesis. Anticonvulsant screening was performed in mice after intraperitoneal administration in the maximal electroshock seizure test (MES) and subcutaneous pentylenetetrazole seizures test (scPTZ). These new compounds showed a wide spectrum activity and were no neurotoxic in the RotoRod test. α-Hydroxyamides and N-derivative-1,2,3-oxathiazolidine-4-one-2,2-dioxides were 3-4700 times more potent than valproic acid in the MES test. Quantification of anticonvulsant protection was calculated (ED(50)) for the most active candidates; α-hydroxyamides 3a-c and 3e, and N-derivative-oxathiazolidine-4-one-2,2-dioxides 5a-c with ED(50) values of 9.1, 53.9, 44.6, 25.2, 15.1, 91.1 and 0.06mg/kg, respectively, in the MES test.
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Affiliation(s)
- Valentina Pastore
- Química Medicinal, Departamento de Ciencias Biológicas, UNLP, calle 47 y 115, B1900BJW La Plata, Argentina.
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Lange W, Geißendörfer J, Schenzer A, Grötzinger J, Seebohm G, Friedrich T, Schwake M. Refinement of the Binding Site and Mode of Action of the Anticonvulsant Retigabine on KCNQ K+ Channels. Mol Pharmacol 2008; 75:272-80. [DOI: 10.1124/mol.108.052282] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Grosso S, Luisi S, Berardi R, Mostardini R, Cordelli DM, Morgese G, Petraglia F, Balestri P. Post-ictal circulating levels of allopregnanolone in children with partial or generalized seizures. Epilepsy Res 2005; 63:97-102. [PMID: 15725389 DOI: 10.1016/j.eplepsyres.2004.12.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2004] [Revised: 12/10/2004] [Accepted: 12/12/2004] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Allopregnanolone (3alpha-hydroxy-5alpha-pregnan-20-one) is a neurosteroid with a potent modulating activity on the gamma-aminobutyric acid (GABA)(a) receptor complex. It plays a key role in the epileptogenesis of partial seizures. Serum allopregnanolone concentrations significantly increase in the postcritical phase. In the present study we investigated the post-ictal serum allopregnanolone levels in children with partial seizures and generalized seizures, respectively. PATIENTS AND METHODS Three groups of subjects were included in the study. Group 1 consisted of 18 children affected by complex partial seizures. Group 2 consisted of 11 children presenting with generalized epilepsy. Group 3 consisted of 20 healthy age-matched subjects. Serum allopregnanolone levels were assayed in the inter-ictal phase and within 30 min after an epileptic event. RESULTS The data we obtained suggest that circulating allopregnanolone level significantly increases in the post-ictal phase. However, we found no significant differences in the post-ictal serum allopregnanolone concentrations between patients with partial seizures and those with generalized seizures. CONCLUSIONS Further studies are needed to establish if allopregnanolone is a reliable circulating marker of epileptic seizures. However, our observations seem to indicate that post-ictal circulating allopregnanolone level is not useful in differentiating focal and generalized epilepsy events.
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Affiliation(s)
- Salvatore Grosso
- Department of Pediatrics, Obstetrics, and Reproductive Medicine, University of Siena, Viale M. Bracci, Le Scotte, 53100 Siena, Italy
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Ross LE, Steiner M. Therapeutic patents for the treatment of premenstrual syndrome and premenstrual dysphoric disorder: historical perspectives and future directions. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.13.10.1491] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Malawska B, Kulig K, Spiewak A, Stables JP. Investigation into new anticonvulsant derivatives of alpha-substituted N-benzylamides of gamma-hydroxy- and gamma-acetoxybutyric acid. Part 5: search for new anticonvulsant compounds. Bioorg Med Chem 2004; 12:625-32. [PMID: 14738973 DOI: 10.1016/j.bmc.2003.10.036] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
A series of four N-benzylamides of gamma-hydroxybutyric acid (GHB), that contain N-(4-phenylpiperazine)-, N-(4-benzylpiperazine)rings, N-benzylamino-, or N-(2-phenylethylamine)-groups in the alpha-position of GHB were selected as model compounds, for determining the structural elements responsible for their potential anticonvulsant action. Based on the results of pharmacological, physicochemical, and molecular modelling investigations, the pharmacophore model for anticonvulsant N-substituted amides of GHB was defined. In this model, the presence of the N-benzylamide fragment is essential for activity. In addition, all of the amides contained another hydrophobic unit (aryl ring) as a distal binding site and H-bond donor. In consideration of these model parameters, a number of N-substituted amides of GHB, containing a hydrophobic moiety such as: N-benzylamino or N-(4-chlorobenzylamino) group in the alpha-position of GHB, and a lipophilic substituent in the amide portion, were prepared. It has been shown that the anticonvulsant activities of the newly synthesized compounds might partially be explained on the basis of their lipophilicity (calculated log P values) and the presence of a hydroxyl group in the molecule.
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Affiliation(s)
- Barbara Malawska
- Department of Pharmaceutical Chemistry, Medical College of Jagiellonian University, Medyczna 9, 30-688 Kraków, Poland.
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Bialer M, Johannessen SI, Kupferberg HJ, Levy RH, Perucca E, Tomson T. Progress report on new antiepileptic drugs: a summary of the Seventh Eilat Conference (EILAT VII). Epilepsy Res 2004; 61:1-48. [PMID: 15570674 DOI: 10.1016/j.eplepsyres.2004.07.010] [Citation(s) in RCA: 142] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The Seventh Eilat Conference on New Antiepileptic Drugs (AEDs) (EILAT VII) took place in Villasimius, Sardinia, Italy from the 9th to 13th May 2004. Basic scientists, clinical pharmacologists and neurologists from 24 countries attended the conference,whose main themes included advances in pathophysiology of drug resistance, new AEDs in pediatric epilepsy syndromes, modes of AED action and spectrum of adverse effects and a re-appraisal of comparative responses to AED combinations. Consistent with previous formats of this conference, the central part of the conference was devoted to a review of AEDs in development, as well as updates on second-generation AEDs. This article summarizes the information presented on drugs in development, including atipamezole, BIA-2-093, fluorofelbamate, NPS 1776, pregabalin, retigabine, safinamide, SPM 927, stiripentol, talampanel,ucb 34714 and valrocemide (TV 1901). Updates on felbamate, gabapentin, lamotrigine, levetiracetam, oxcarbazepine, tiagabine,topiramate, vigabatrin, zonisamide, new oral and parenteral formulations of valproic acid and SPM 927 and the antiepileptic vagal stimulator device are also presented.
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Affiliation(s)
- Meir Bialer
- Department of Pharmaceutics, Faculty of Medicine, School of Pharmacy and David R. Bloom Center for Pharmacy, The Hebrew University of Jerusalem, Jerusalem, Israel.
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Abstract
Up to 70% of people developing epilepsy may expect to become seizure free with optimum antiepileptic drug (AED) therapy. The remaining 30% are the most difficult to treat. Most patients are controlled on a single AED, but a small proportion requires a combination of two agents. Add-on therapy with a second drug, rather than substitution, may be a viable and rational approach in some patients, particularly if the first drug is relatively well tolerated. Precise classification of the type of seizures, as well as the epilepsy syndrome, together with careful recording of both seizures and adverse effects, are essential if rational management decisions are to be made. The goal of therapy should be complete seizure freedom with a single drug taken once or twice a day and without adverse effects. If control is difficult to achieve, the maximum tolerated dose of each drug should be explored, but a balance needs to be struck between adverse effects and control of seizures. In patients in whom treatment appears to be ineffective, the diagnosis of epilepsy and adherence to therapy should be reviewed. Drugs used in combination must be carefully selected, as poor adherence, drug interactions, and toxicity are more likely if more than one drug is prescribed. Agents are usually chosen according to seizure type, patient characteristics, and often by clinician preference. Those that are better tolerated have a low potential for pharmacokinetic and pharmacodynamic interactions, and those that can be easily introduced without any complicated titration schedule have an advantage.
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Affiliation(s)
- Josemir W Sander
- Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, London WC1N 3BG, UK.
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Abstract
PURPOSE The aim of our research was to study some biochemical modifications elicited in primary rat astrocyte cultures by treatment with gabapentin (GBP), carbamazepine (CBZ), lamotrigine (LTG), topiramate (TPM), oxcarbazepine (OXC), tiagabine (TGB), and levetiracetam (LEV), commonly used in the treatment of epilepsy. We investigated the biologic effects of these anticonvulsants (AEDs) at concentrations of 1, 10, 50, and 100 microg/ml. METHODS The study was performed by examining cell viability (MTT assay), cell toxicity [lactate dehydrogenase (LDH) release in the medium], glutamine synthetase (GS) activity, reactive oxygen species (ROS) production, lipoperoxidation level (malondialdehyde; MDA), and DNA fragmentation (COMET assay). The level of the expression of 70-kDa heat-shock protein (HSP70) and inducible nitric oxide synthase (iNOS) as oxidative stress-modulated genes also was determined. RESULTS Our experiments indicate that CBZ, TPM, and OXC induce stress on astrocytes at all concentrations. GBP, LTG, TGB, and LEV, at low concentrations, do not significantly change the metabolic activities examined and do not demonstrate toxic actions on astrocytes. They do so at higher concentrations. CONCLUSIONS Most AEDs have effects on glial cells and, when used at an appropriate cell-specific concentrations, may be well tolerated by cortical astrocytes. However, at higher concentrations, GBP, LTG, TGB, and LEV seem to be better tolerated than are CBZ, TPM, and OXC. These findings may reveal novel ways of producing large numbers of new AEDs capable of reducing the extent of inflammation, neuronal damage, and death under pathological conditions such as epilepsy and/or traumatic brain injury.
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Austin NE, Hadley MS, Harling JD, Harrington FP, Macdonald GJ, Mitchell DJ, Riley GJ, Stean TO, Stemp G, Stratton SC, Thompson M, Upton N. The design of 8,8-dimethyl[1,6]naphthyridines as potential anticonvulsant agents. Bioorg Med Chem Lett 2003; 13:1627-9. [PMID: 12729628 DOI: 10.1016/s0960-894x(03)00288-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Starting from a series of 7-linked tetrahydroisoquinoline derivatives, as exemplified by SB-270664, a new series of 8,8-dimethylnaphthyridine compounds has been identified. SAR studies around these attractive leads have provided compounds such as 12 which display excellent anticonvulsant activity and an encouraging pharmacokinetic profile in vivo.
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Affiliation(s)
- Nigel E Austin
- Neurology & GI Centre of Excellence for Drug Discovery, GlaxoSmithKline Research & Development Limited, New Frontiers Science Park, Third Avenue, Harlow, Essex CM19 5AW, UK
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Rekling JC. Neuroprotective effects of anticonvulsants in rat hippocampal slice cultures exposed to oxygen/glucose deprivation. Neurosci Lett 2003; 335:167-70. [PMID: 12531459 DOI: 10.1016/s0304-3940(02)01193-x] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Some anticonvulsants show neuroprotective effects, and may be of use in reducing neuronal death resulting from stroke or traumatic brain injury. Here I report that a broad range of anticonvulsants protect cells in hippocampal slice cultures from death induced by oxygen/glucose deprivation (OGD). Hippocampal slice cultures were submitted to 1 h OGD and the resulting cell death was quantified 24 h later using a novel automated fluorescent scanning method. The classical anticonvulsants phenobarbital, phenytoin, ethosuximide, chlordiazepoxide and midazolam all significantly and dose-dependently reduced cell death induced by OGD. The newer anticonvulsants carbamazepine, felbamate, lamotrigine, tiagabine, and oxcarbazepine also had significant neuroprotective effects, but gabapentin, valproic acid (10 mM), levetiracetam and retigabine were not neuroprotective at a concentration up to 300 microM. In conclusion, several classical and newer anticonvulsants have neuroprotective properties in an in vitro model that simulates cerebral ischemia.
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Affiliation(s)
- Jens C Rekling
- H. Lundbeck A/S, Biological Research, Department 828, Ottiliavej 9, DK-2500 Valby, Denmark.
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De Sarro G, Chimirri A, Meldrum BS. Group III mGlu receptor agonists potentiate the anticonvulsant effect of AMPA and NMDA receptor block. Eur J Pharmacol 2002; 451:55-61. [PMID: 12223229 DOI: 10.1016/s0014-2999(02)02004-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We report the anticonvulsant action in DBA/2 mice of two mGlu Group III receptor agonists: (R,S)-4-phosphonophenylglycine, (R,S)-PPG, a compound with moderate mGlu8 selectivity, and of (1S,3R,4S)-1-aminocyclopentane-1,2,4-tricarboxylic acid, ACPT-1, a selective agonist for mGlu4alpha receptors. Both compounds, given intracerebroventricularly at doses which did not show marked anticonvulsant activity, produced a consistent shift to the left of the dose-response curves (i.e. enhanced the anticonvulsant properties) of 1-(4'-aminophenyl)-3,5-dihydro-7,8-dimethoxy-4H-2,3-benzodiazepin-4-one hydrochloride, CFM-2, a noncompetitive AMPA receptor antagonist, and 3-((+/-)-2-carboxypiperazin-4-yl)-1-phosphonic acid, CPPene, a competitive NMDA receptor antagonist, in DBA/2 mice. In addition, (R,S)-PPG and ACPT-1 administered intracerebroventricularly prolonged the time course of the anticonvulsant properties of CFM-2 (33 micromol/kg, i.p.) and CPPene (3.3 micromol/kg, i.p.) administered intraperitoneally. We conclude that modest reduction of synaptic glutamate release by activation of Group III metabotropic receptors potentiates the anticonvulsant effect of AMPA and NMDA receptor blockade.
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Affiliation(s)
- Giovambattista De Sarro
- Cattedra di Farmacologia, Dipartimento di Medicina Sperimentale e Clinica, Università di Catanzaro, Catanzaro, Italy
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&NA;. Dosage optimisation difficult but crucial to optimal management of epilepsy. DRUGS & THERAPY PERSPECTIVES 2002. [DOI: 10.2165/00042310-200218070-00005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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