21 results on '"Limmroth, V."'
Search Results
2. Weekly IM interferon beta‐1a in multiple sclerosis patients over 50 years of age
- Author
-
Lampl, C., primary, You, X., additional, and Limmroth, V., additional
- Published
- 2011
- Full Text
- View/download PDF
3. Efficacy of natalizumab in second line therapy of relapsing-remitting multiple sclerosis: results from a multi-center study in German speaking countries
- Author
-
Putzki, N., primary, Yaldizli, O., additional, Mäurer, M., additional, Cursiefen, S., additional, Kuckert, S., additional, Klawe, C., additional, Maschke, M., additional, Tettenborn, B., additional, and Limmroth, V., additional
- Published
- 2009
- Full Text
- View/download PDF
4. Natalizumab is effective as second line therapy in the treatment of relapsing remitting multiple sclerosis
- Author
-
Putzki, N., primary, Kollia, K., additional, Woods, S., additional, Igwe, E., additional, Diener, H. C., additional, and Limmroth, V., additional
- Published
- 2009
- Full Text
- View/download PDF
5. Prevalence of migraine, tension‐type headache and trigeminal neuralgia in multiple sclerosis
- Author
-
Putzki, N., primary, Pfriem, A., additional, Limmroth, V., additional, Yaldizli, Ö., additional, Tettenborn, B., additional, Diener, H. C., additional, and Katsarava, Z., additional
- Published
- 2009
- Full Text
- View/download PDF
6. Relapsing neuromyelitis optica responsive to glatiramer acetate treatment
- Author
-
Gartzen, K, primary, Limmroth, V, additional, and Putzki, N, additional
- Published
- 2007
- Full Text
- View/download PDF
7. NEW ANTI‐MIGRAINE DRUGS: PRESENT AND BEYOND THE MILLENNIUM
- Author
-
Limmroth, V, primary and Diener, HC, additional
- Published
- 1998
- Full Text
- View/download PDF
8. Weekly IM interferon beta-1a in multiple sclerosis patients over 50 years of age.
- Author
-
Lampl C, You X, and Limmroth V
- Subjects
- Adolescent, Adult, Aged, Clinical Trials, Phase II as Topic, Clinical Trials, Phase III as Topic, Humans, Injections, Intramuscular, Interferon beta-1a, Middle Aged, Multicenter Studies as Topic, Young Adult, Adjuvants, Immunologic administration & dosage, Interferon-beta administration & dosage, Multiple Sclerosis drug therapy
- Abstract
Background: Efficacy and safety data have not previously been compiled for intramuscular interferon beta-1a (IM IFNβ-1a) in patients with multiple sclerosis (MS) ≥ 50 years of age. We investigated the efficacy and safety of IM IFNβ-1a in patients segregated by 50 and 40 years of age in separate meta-analyses., Methods: The MS Clinical Research Group Study, the Controlled High-Risk Subjects AVONEX(®) (IM IFNβ-1a) MS Prevention Study, the IFNβ-1a European Dose-Comparison Study, and a multicenter, open-label antigenicity and safety study of human serum albumin-free IM IFNβ-1a were analyzed., Results: Overall, 906 patients (68 aged ≥ 50 years and 838 aged <50 years, or 323 aged ≥ 40 years and 583 aged <40 years) received IM IFNβ-1a for ≥ 24 months. At baseline, patients ≥ 50 years had significantly higher Expanded Disability Status Scale scores than patients <50 years (3.4 vs. 2.8; P < 0.001), but fewer relapses in the three preceding years (2.6 vs. 3.4; P < 0.001); patients ≥ 40 years and <40 years exhibited similar differences. After 2 years of treatment, there were no significant differences in annualized relapse rate, sustained disability progression, time to sustained disability progression, or number of MRI-identified gadolinium-enhanced lesions between age groups in either analysis. The cumulative probability of relapse was significantly lower in patients ≥ 40 years versus patients <40 years (0.601 vs. 0.702; P < 0.001). Adverse event incidence did not differ significantly between age groups in either analysis., Conclusions: IM IFNβ-1a is effective and well tolerated in patients with MS ≥ 40 and ≥ 50 years as well as younger patients., (© 2011 The Author(s). European Journal of Neurology © 2011 EFNS.)
- Published
- 2012
- Full Text
- View/download PDF
9. Frovatriptan for prophylactic treatment of cluster headache: lessons for future trial design.
- Author
-
Pageler L, Katsarava Z, Lampl C, Straube A, Evers S, Diener HC, and Limmroth V
- Subjects
- Carbazoles adverse effects, Double-Blind Method, Endpoint Determination, Guidelines as Topic, Humans, Patient Selection, Research Design, Serotonin Agents adverse effects, Tryptamines adverse effects, Carbazoles therapeutic use, Cluster Headache prevention & control, Serotonin Agents therapeutic use, Tryptamines therapeutic use
- Abstract
Objective: The aim of this study was to determine whether frovatriptan would show efficacy in short term prophylactic treatment of episodic cluster headache (ECH) in comparison to placebo., Background: The 5-hydroxytryptamine(1B/d) (5-HT(1B/d) )-agonists naratriptan, eletriptan, and frovatriptan have been shown to reduce the frequency of ECH. So far, no double-blind placebo-controlled trials have investigated the potential prophylactic effects of 5-HT(1B/d) -agonists in ECH., Methods: The trial was conducted as a multi-center, placebo-controlled, randomized, double-blind, prospective phase III parallel-group trial with two independent treatment groups (5 mg frovatriptan vs placebo). It was planned to randomize about 96 patients (48 patients per group) into the trial to obtain 80 evaluable patients (40 patients per group)., Results: The study was prematurely discontinued after 13 months and enrollment of 11, instead of the planned 80 patients, by the sponsor due to infeasibility. Recruitment was slow and each of the patients included conducted major protocol violations. The differences in the primary and secondary endpoints were not significant., Conclusion: This study shows that particular therapeutic aims are impossible to be addressed in a double-blind, randomized, parallel group, study design with specific inclusion and exclusion criteria according to the International Headache Society (IHS) guidelines for controlled trials of drugs in cluster headache. Further studies are required to evaluate the potential efficacy of triptans in the prophylactic treatment of ECH. The outcome of the trial suggests that the recommendations of the Guidelines for controlled Trials of Drugs in Cluster Headache from the IHS should be revised., (© 2010 American Headache Society.)
- Published
- 2011
- Full Text
- View/download PDF
10. Single nucleotide polymorphisms of the serotonin transporter gene in migraine--an association study.
- Author
-
Bayerer B, Engelbergs J, Savidou I, Boes T, Küper M, Schorn CF, Wissmann A, Knop D, Diener HC, and Limmroth V
- Subjects
- Brain metabolism, Brain physiopathology, Brain Chemistry genetics, Case-Control Studies, DNA Mutational Analysis, Female, Gene Frequency genetics, Genetic Markers genetics, Genetic Testing, Genotype, Humans, Male, Migraine Disorders physiopathology, Genetic Predisposition to Disease genetics, Migraine Disorders genetics, Migraine Disorders metabolism, Polymorphism, Single Nucleotide genetics, Serotonin metabolism, Serotonin Plasma Membrane Transport Proteins genetics
- Abstract
We report a case-control study with 251 unrelated migraine patients and 192 unrelated healthy controls to evaluate an association between the polymorphisms of the 5-HT transporter (5-HTT) gene rs2066713 and rs1979572 and different migraine phenotypes. We found a genetic association for the A allele of rs1979572 for migraine with aura (MA) especially in women as well as a significant lower prevalence for MA for carrier of the A allele of rs2066713 in women. These findings support previous results suggesting that the 5-HTT gene is involved in the polygenic etiology of MA. These data further suggest that women are more likely to be clinically affected by mutations in the 5-HTT gene than men.
- Published
- 2010
- Full Text
- View/download PDF
11. Efficacy of natalizumab in second line therapy of relapsing-remitting multiple sclerosis: results from a multi-center study in German speaking countries.
- Author
-
Putzki N, Yaldizli O, Mäurer M, Cursiefen S, Kuckert S, Klawe C, Maschke M, Tettenborn B, and Limmroth V
- Subjects
- Adult, Antibodies, Monoclonal adverse effects, Antibodies, Monoclonal, Humanized, Central Nervous System immunology, Central Nervous System pathology, Contrast Media, Disability Evaluation, Female, Gadolinium, Germany, Glatiramer Acetate, Humans, Immunologic Factors adverse effects, Immunologic Factors therapeutic use, Immunosuppressive Agents therapeutic use, Interferon-beta therapeutic use, Magnetic Resonance Imaging, Male, Middle Aged, Multiple Sclerosis, Relapsing-Remitting immunology, Multiple Sclerosis, Relapsing-Remitting pathology, Natalizumab, Outcome Assessment, Health Care, Peptides therapeutic use, Retrospective Studies, Secondary Prevention, Severity of Illness Index, Treatment Failure, Young Adult, Antibodies, Monoclonal administration & dosage, Central Nervous System drug effects, Drug Resistance immunology, Immunologic Factors administration & dosage, Multiple Sclerosis, Relapsing-Remitting drug therapy
- Abstract
Background: Natalizumab has been recommended for the treatment of relapsing-remitting multiple sclerosis (RRMS) in patients with insufficient response to interferon-beta/glatiramer acetate (DMT) or aggressive MS. The pivotal trials were not conducted to investigate natalizumab monotherapy in this patient population., Method: Retrospective, multicenter study in Germany and Switzerland. Five major MS centers reported all RRMS patients who initiated natalizumab >or=12 months prior to study conduction., Results: Ninety-seven RRMS patients were included [69% female, mean age 36.5 years, mean Expanded Disability Status Scale (EDSS) 3.4; 93.8% were pre-treated with DMT], mean treatment duration with natalizumab was 19.3 +/- 6.1 months. We found a reduction of the annualized relapse rate from 2.3 to 0.2, 80.4% were relapse free with natalizumab. EDSS improved in 12.4% and 89.7% were progression free (change of >or= 1 EDSS point). Eighty-six per cent of patients with highly active disease (>or= 2 relapses in the year and >or= 1 Gadolinium (Gd)+ lesion at study entry, n = 20) remained relapse free. The mean number of Gd enhancing lesions was reduced to 0.1 (0.8 at baseline). Discontinuation rate was 8.2% (4.1% for antibody-positivity)., Conclusion: Natalizumab is effective after insufficient response to other DMT and also in patients with high disease activity.
- Published
- 2010
- Full Text
- View/download PDF
12. Retropharyngeal tendinitis: a rare differential diagnosis of severe headaches and neck pain.
- Author
-
Harnier S, Kuhn J, Harzheim A, Bewermeyer H, and Limmroth V
- Subjects
- Adult, Diagnosis, Differential, Female, Humans, Headache etiology, Neck Pain etiology, Pharyngeal Diseases complications, Pharyngeal Diseases diagnosis, Tendinopathy complications, Tendinopathy diagnosis
- Abstract
Retropharyngeal tendinitis is a rare cause of intense neck pain and occipital headache. It is caused by an aseptic inflammatory process in the longus colli tendon, triggered by deposition of calcium hydroxyapatite crystal. Clinically, it can be misdiagnosed as retropharyngeal abscess, traumatic injury, infectious spondylitis, cervical artery dissection, or even meningitis. The diagnosis is made radiographically by a nearly pathognomonic amorphous calcification anterior to C1-C2 and prevertebral soft tissue swelling. We present a new case of this uncommon condition exhibiting some unusual features.
- Published
- 2008
- Full Text
- View/download PDF
13. Association between migraine and the G1246A polymorphism in the hypocretin receptor 2 gene.
- Author
-
Schürks M, Limmroth V, Geissler I, Tessmann G, Savidou I, Engelbergs J, Kurth T, Diener HC, and Rosskopf D
- Subjects
- Adult, Chi-Square Distribution, DNA Mutational Analysis, Female, Humans, Male, Middle Aged, Orexin Receptors, Retrospective Studies, Alanine genetics, Genetic Predisposition to Disease, Glycine genetics, Migraine Disorders genetics, Polymorphism, Genetic genetics, Receptors, G-Protein-Coupled genetics, Receptors, Neuropeptide genetics
- Abstract
Background: The hypocretin receptor 2 (HCRTR2) G1246A polymorphism has been associated with the risk for cluster headache. Since the hypothalamic hypocretin/orexin system projects throughout the nervous system and affects multiple vegetative functions including generation of rhythmicity, vasomotion, autonomic symptoms as well as modulation of nociception, it may also be linked with migraine., Objective: We thus sought to evaluate whether the HCRTR2 G1246A polymorphism is associated with the risk for migraine., Methods: We prospectively established a cohort of 146 unrelated patients with migraine. The control group consisted of 279 healthy volunteers. We genotyped patients and controls for the HCRTR2 G1246A polymorphism and examined an association with presence or absence of migraine., Results: Genotype and allele frequencies were not significantly different between migraine patients and controls (genotype distribution: chi(2)= 4.13, 2 df, P= .13; allele distribution: chi(2)= 0.9, 1 df, P= .34)., Conclusion: Our study does not support a major contribution of the HCRTR2 G1246A polymorphism to the pathogenesis of migraine in contrast to its effects in cluster headache.
- Published
- 2007
- Full Text
- View/download PDF
14. Topiramate in patients with episodic migraine: reducing the risk for chronic forms of headache.
- Author
-
Limmroth V, Biondi D, Pfeil J, and Schwalen S
- Subjects
- Adolescent, Adult, Aged, Child, Double-Blind Method, Female, Fructose therapeutic use, Headache Disorders etiology, Humans, Male, Middle Aged, Migraine Disorders complications, Odds Ratio, Prospective Studies, Risk Factors, Topiramate, Treatment Outcome, Fructose analogs & derivatives, Headache Disorders prevention & control, Migraine Disorders drug therapy, Neuroprotective Agents therapeutic use
- Abstract
Objective: The aim was to evaluate whether preventive treatment with topiramate in patients with episodic migraine reduces the risk of developing chronic forms of headache., Background: Chronic forms of headache, including chronic migraine or medication overuse headache (MOH), are characterized by 15 or more headache days per month. Acute medication overuse has been shown to be a risk factor for developing chronic headache, but it is not known whether preventive treatment can reduce the risk of developing chronic forms of headache or the development of MOH., Methods: Pooled data from 3 trials in patients with episodic migraine randomized either to treatment with 100 mg topiramate per day (n = 384) or with placebo (n = 372) were analyzed with regard to the number of headache days during a prospective 4-week baseline period and the individual final 4 weeks of each patient's treatment during the planned 26-week double-blind treatment period., Results: The number of headache days per month in the topiramate versus the placebo-treated groups was 7.3 +/- 3.0 versus 7.3 +/- 3.1 during baseline and 4.1 +/- 4.2 versus 5.6 +/- 4.9 during the final 4 weeks, respectively (P < .001). At the end of the study, 8 versus 16 patients fulfilled International Headache Society criteria of chronic headache (odds ratio: 2.11, P= .082). Moreover, a significantly lower number of patients receiving topiramate treatment reported an increase in headache days per month by the end of the study when compared to placebo (66 vs 88 patients, respectively; odds ratio: 1.49, P < .05). Finally, the number of days with usage of acute medication was significantly lower in the topiramate arm compared with placebo (3.3 +/- 3.7 vs 4.3 +/- 3.6, respectively; P < .001)., Conclusion: Preventive treatment with topiramate in patients with episodic migraine may reduce the risk of developing chronic forms of headache.
- Published
- 2007
- Full Text
- View/download PDF
15. A novel method of eliciting pain-related potentials by transcutaneous electrical stimulation.
- Author
-
Katsarava Z, Ayzenberg I, Sack F, Limmroth V, Diener HC, and Kaube H
- Subjects
- Adult, Anesthesia, Local, Evoked Potentials physiology, Female, Humans, Male, Neural Conduction physiology, Neurons, Afferent physiology, Nociceptors physiology, Pain Measurement, Pain physiopathology, Transcutaneous Electric Nerve Stimulation
- Abstract
Background: Electrophysiological techniques such as laser and contact heat evoked pain-related potentials are very useful for studying trigeminal and somatic pain transmission in humans. These methods are, however, partly invasive, expensive, and therefore not available for broad clinical use. We recently proposed a novel technique of noninvasive transcutaneous electrical stimulation., Objective: To elicit pain-related evoked potentials (PREP) by using a concentric planar electrode and demonstrate their nociceptive specificity., Methods: We registered PREP following stimulation of the forehead and hand in 14 healthy volunteers. Latencies, peak-to-peak amplitudes, and conduction velocities of nociceptive fibers have been estimated. Effects of temporal and spatial summation and of cutaneous anesthesia were evaluated., Results: Stimulation with the concentric planar electrode produced pinprick-like painful sensation. Cutaneous anesthesia led to abolishment of PREP responses. Estimated mean conduction velocity was 11.61 +/- 5.12 m/s, which corresponded well with conduction via A-delta fibers. Spatial as well as temporal summation resulted in a parallel increase of perceived pain intensity and PREP amplitudes., Conclusion: The technique is noninvasive, affordable, and easy to perform and allows quantitative assessment of human nociceptive pathways.
- Published
- 2006
- Full Text
- View/download PDF
16. Company reference estimates for productivity loss due to migraine and productivity gains using rizatriptan 10 mg in Germany.
- Author
-
Yoon MS, Katsarava Z, Liedert B, Krobot KJ, Diener HC, and Limmroth V
- Subjects
- Absenteeism, Adult, Aged, Cost of Illness, Female, Germany epidemiology, Humans, Male, Middle Aged, Migraine Disorders economics, Migraine Disorders epidemiology, Prevalence, Serotonin Receptor Agonists economics, Triazoles economics, Tryptamines economics, Efficiency, Migraine Disorders drug therapy, Serotonin Receptor Agonists therapeutic use, Triazoles therapeutic use, Tryptamines therapeutic use
- Abstract
The prevalence of migraine in Germany is up to 14% in the female and up to 8% in the male population and peaks between the age of 35 and 45. Few studies have investigated the productivity loss and resulting costs attributable to migraine in Germany or addressed the question whether these costs can be reduced by optimal treatment. In recent years, 5-HT(1B/D) agonists (so-called triptans), a generation of drugs highly specific for migraine treatment, have been introduced. Seven 5-HT(1B/D) agonists have been approved in Germany with more than 20 dosage forms. We present a model that enables employers to estimate the annual cost of migraine and the annual cost that could be saved by treatment of migraine with rizatriptan compared with the use of non-specific antimigraine medication. A representative German company with 10,000 employees is used for the reference case analysis. This company is predicted to have 580 female and 284 male employees with migraine. These employees are estimated to lose 6992 workdays or 31.8 person years of productive effort annually due to migraine, valued approximately 1,431,719 euros. The value of work loss that could be avoided by treating migraine with rizatriptan is estimated at 619,094 euros annually. These data indicate that costs arising from lost productivity can be reduced by treating migraine headaches with a triptan.
- Published
- 2006
- Full Text
- View/download PDF
17. Comparison of intravenous valproate with intravenous lysine-acetylsalicylic acid in acute migraine attacks.
- Author
-
Leniger T, Pageler L, Stude P, Diener HC, and Limmroth V
- Subjects
- Acute Disease, Double-Blind Method, Humans, Infusions, Intravenous, Treatment Outcome, Analgesics administration & dosage, Aspirin administration & dosage, Aspirin analogs & derivatives, GABA Agents administration & dosage, Lysine administration & dosage, Lysine analogs & derivatives, Migraine Disorders drug therapy, Valproic Acid administration & dosage
- Abstract
Objective: The study compared efficacy and tolerability of intravenous valproate (iVPA) with intravenous lysine-acetylsalicylic acid (iLAS) in acute migraine attacks. Background.-iLAS has been proven to be a highly effective treatment in acute migraine attacks, but it is not available in many countries and contraindicated in patients with asthma or peptic ulcers. Current data suggest that iVPA may be effective in the treatment of acute migraine attacks., Design/methods: In this randomized, double-blind, parallel-group phase-II study, 40 patients with acute migraine attacks (onset <5 hours, severe or moderate headache on a four-point IHS scale) alternately received iVPA 800 mg or iLAS 1000 mg. Primary outcome criteria were the percentage of patients reporting pain relief after 1 hour and patients who remained sustained pain free for 24 hours following drug administration. Secondary outcome criteria were relief of pain and associated migrainous symptoms (nausea, photophobia, and phonophobia) at 1, 2, 24, and 48 hours following drug administration., Results: There were no significant differences in demographic and clinical features between both treatment groups. Percentage of pain relief after 1 hour in the iVPA and iLAS groups were 25% and 30%, respectively, and of sustained pain free for 24 hours were 20% and 30%, respectively, without significant differences (P = 1 and P= .72, respectively). Both drugs improved associated migrainous symptoms without significant differences at the different time points, but again with a trend in favor of iLAS. No adverse events were observed., Conclusion: Both drugs were effective in acute migraine attacks with a trend in favor of iLAS. As both drugs were well tolerated, further studies with higher doses of iVPA for the treatment of acute migraine attacks are recommended.
- Published
- 2005
- Full Text
- View/download PDF
18. GABAA-receptor-mediated effects of progesterone, its ring-A-reduced metabolites and synthetic neuroactive steroids on neurogenic oedema in the rat meninges.
- Author
-
Limmroth V, Lee WS, and Moskowitz MA
- Subjects
- Animals, Bicuculline pharmacology, Brain Edema etiology, Capillary Permeability drug effects, Dose-Response Relationship, Drug, Female, GABA Antagonists pharmacology, Isomerism, Male, Meninges metabolism, Pregnanolone pharmacology, Progesterone therapeutic use, Rats, Rats, Sprague-Dawley, Serum Albumin, Bovine, Substance P pharmacology, Brain Edema drug therapy, Meninges drug effects, Progesterone pharmacology, Receptors, GABA-A drug effects
- Abstract
1. The effects of progesterone, its A-ring-reduced metabolites, allopregnanolone, tetrahydroxydeoxycorticosterone and the synthetic neuroactive steroid alphaxalone were evaluated in a rat model of plasma extravasation within the meninges following unilateral electrical stimulation (ES) of the trigeminal ganglion (0.6 mA, 5 ms, 5 min) or substance P administration (1 nmol kg-1, i.v.). 2. When administered 55 min prior to electrical stimulation, progesterone (> or = 500 micrograms, s.c.) dose-dependently decreased plasma extravasation within the meninges (ED50: 650 micrograms) but not within conjunctiva and tongue. Promegestone (R5020), a non-metabolized progesterone agonist (1000 micrograms, i.p.) was ineffective. The administration of progestrone (> or = 500 micrograms s.c.) 55 min prior to substance P partially suppressed plasma extravasation within the meninges (ED50: 550 micrograms). 3. The GABAA-antagonist, bicuculline (ED50: 8.2 micrograms kg-1, i.p.) but not the GABAB-antagonist, phaclofen (100 micrograms kg-1, i.p.) attenuated the effects of progesterone after electrical stimulation and substance P administration. 4. The metabolites of progesterone, allopregnanolone (3 alpha-hydroxy-5 alpha- pregnan-20-one (THP); ED50: 0.58 micrograms kg-1, i.p.), tetrahydroxydeoxycorticosterone (3 alpha,21- dihydroxy-5 alpha-pregnan-20-one (THDOC); ED50: 1.2 micrograms kg-1, i.p.) as well as the synthetic steroid alphaxalone (3 alpha-hydroxy-5 alpha-pregnane-11,20-dione; ED50: 1.8 micrograms kg-1, i.p.) suppressed plasma extravasation dose-dependently following ES, whereas the epimer of allopregnanolone, 3 beta-hydroxy-5 alpha-pregnan-20-one (100 micrograms kg-1, i.p.), did not. Extravasation caused by SP administration was partially suppressed by allopregnanolone (> or = 1 microgram kg-1, i.p.) (ED50: 2.1 micrograms kg-1). 5. The effect of progesterone (1000 micrograms, s.c.) and allopregnanolone (100 micrograms kg-1, i.p.) on neurogenic plasma extravasation was reversed by bicuculline (10 micrograms kg-1, i.p.) or by a congener, bicuculline-methiodide (10 micrograms kg-1, i.p.) which does not cross the blood brain barrier. 6. Progesterone (1000 micrograms, s.c.) had no effect on mean arterial blood pressure or heart rate when measured for 60 min after administration. 7. These results indicate that neurosteroid modulation of a GABAA-receptor located outside the blood brain barrier suppresses neurogenic and substance P-induced plasma extravasation within the meninges. The findings are consistent with previously reported data showing that valproic acid and muscimol inhibit meningeal oedema by bicuculline-sensitive mechanisms. Drugs which activate GABAA-receptors and its modulatory sites might be clinically effective in the treatment of migraine and cluster headache.
- Published
- 1996
- Full Text
- View/download PDF
19. Attenuation by valproate of c-fos immunoreactivity in trigeminal nucleus caudalis induced by intracisternal capsaicin.
- Author
-
Cutrer FM, Limmroth V, Ayata G, and Moskowitz MA
- Subjects
- Animals, Baclofen analogs & derivatives, Baclofen pharmacology, Bicuculline pharmacology, Brain Stem drug effects, GABA Antagonists pharmacology, Guinea Pigs, Injections, Intraventricular, Male, Trigeminal Nuclei metabolism, Capsaicin antagonists & inhibitors, GABA Agents pharmacology, Proto-Oncogene Proteins c-fos biosynthesis, Trigeminal Nuclei drug effects, Valproic Acid pharmacology
- Abstract
1. Valproic acid, useful in the treatment of migraine, is an inhibitor of gamma aminobutyric acid (GABA) aminotransferase and activator of glutamic acid decarboxylase. Its mechanism in migraine remains obscure. The effects of valproic acid (2-propylpentanoic acid) were examined on the number of cells expressing c-fos-like immunoreactivity (c-fos-LI), a marker of neuronal activation, within the trigeminal nucleus caudalis (lamina I, IIo, TNC) 2 h after intracisternal injection of the irritant, capsaicin (0.1 ml; 15.25 micrograms ml-1), in urethane-anaesthetized Hartley guinea-pigs. Positive cells were counted in eighteen sections (50 microns) at three representative levels (rostral, middle and caudal) within lamina I, IIo of the TNC in 90 animals. 2. Numerous cells were labelled after capsaicin instillation (244 +/- 25; 1 ml; 15.25 mM) but not after capsaicin vehicle (11 +/- 1). Positive cells were also found within the medial reticular nucleus, the area postrema and the nucleus of the solitary tract. A similar distribution has been demonstrated previously after application of intracisternal irritants such as autologous blood or carrageenin. 3. Valproate (> or = 10 mg kg-1, i.p.) reduced labelled cells by 52% (P < 0.05) in lamina I, IIo but not within the area postrema, the nucleus of the solitary tract or the medial reticular nucleus. A similar finding was obtained previously after administration of sumatriptan, dihydroergotamine or the NK1 receptor antagonist RPR 100,893. 4. Pretreatment with bicuculline (30 micrograms kg-1; i.p.), a GABAA antagonist, but not phaclofen (1 mg kg-1) a GABAB antagonist, reversed the effect of valproate and increased c-fos positive cells within lamina I, IIo. Somewhat paradoxically, bicuculline by itself (30 micrograms kg-1 i.p.) decreased the number of labelled cells suggesting that more than a single GABAergic mechanism can suppress c-fos expression. 5. We conclude that the mechanism of action of valproate is mediated via GABAA receptors. Since valproate decreases both c-fos expression and as previously shown, neurogenic inflammation within the meninges, the GABAA receptor complex might provide an important target for drug development in migraine and related headaches.
- Published
- 1995
- Full Text
- View/download PDF
20. Peripheral GABAA receptor-mediated effects of sodium valproate on dural plasma protein extravasation to substance P and trigeminal stimulation.
- Author
-
Lee WS, Limmroth V, Ayata C, Cutrer FM, Waeber C, Yu X, and Moskowitz MA
- Subjects
- Animals, Baclofen pharmacology, Blood Pressure drug effects, Capsaicin pharmacology, Electric Stimulation, GABA Agonists pharmacology, GABA-A Receptor Agonists, GABA-A Receptor Antagonists, Heart Rate drug effects, Iodine Radioisotopes, Male, Muscimol pharmacology, Neuritis blood, Rats, Rats, Sprague-Dawley, Capillary Permeability drug effects, Dura Mater blood supply, Extravasation of Diagnostic and Therapeutic Materials, GABA Agents pharmacology, Neuritis drug therapy, Receptors, GABA-A physiology, Serum Albumin, Bovine pharmacokinetics, Substance P pharmacology, Trigeminal Ganglion physiology, Valproic Acid pharmacology
- Abstract
1. The GABA transaminase inhibitor and activator of glutamic acid decarboxylase, valproic acid is being used for the treatment of migraine. Its mechanism of action is unknown. We tested the effects of sodium valproate and GABAA-agonist muscimol on dural plasma protein ([125I]-bovine serum albumin) extravasation evoked by either unilateral trigeminal ganglion stimulation (0.6 mA, 5 ms, 5 Hz, 5 min) or substance P (SP) administration (1 nmol kg-1,i.v.) in anaesthetized Sprague-Dawley rats. 2. Intraperitoneal (i.p.) injection of sodium valproate or muscimol, but not baclofen (< or = 10 mg kg-1, i.p.) dose-dependently reduced dural plasma protein extravasation caused either by electrical trigeminal stimulation (ED50: 6.6 +/- 1.4 mg kg-1, i.p., and 58 +/- 18 micrograms kg-1, i.p. for valproate or muscimol, respectively) or by intravenous substance P administration (ED50: 3.2 +/- 1.4 mg kg-1, i.p. and 385 +/- 190 micrograms kg-1, i.p. for valproate or muscimol, respectively). 3. Valproate (6.6 mg kg-1, i.p.) or muscimol (58 micrograms kg-1, i.p.) had no effect on mean arterial blood pressure or heart rate when measured for 30 min after i.p. administration. 4. The GABAA-antagonist bicuculline (0.01 mg kg-1, i.p.) completely reversed the effect of valproate and muscimol on plasma extravasation following electrical stimulation or substance P administration, whereas the GABAB-receptor antagonist, phaclofen (0.01-1 mg kg-1, i.p.) did not. Bicuculline or phaclofen, given alone, did not alter the plasma extravasation response after either electrical stimulation or SP administration. 5. Valproate decreased plasma extravasation following substance P administration in adult animals, neonatally treated with capsaicin by a bicuculline-reversible mechanism. This suggests that GABAA receptors are not found primarily on those afferent neurones or fibres which are sensitive to capsaicin treatment in neonatal rats.6. We conclude that sodium valproate blocks plasma extravasation in the meninges through GABAA mediated postjunctional receptors probably within the meninges. The dosages required are comparable to those used clinically. Agonists and modulators at the GABAA receptor may become useful for the development of selective therapeutic agents for migraine and cluster headache.
- Published
- 1995
- Full Text
- View/download PDF
21. Suppression by the sumatriptan analogue, CP-122,288 of c-fos immunoreactivity in trigeminal nucleus caudalis induced by intracisternal capsaicin.
- Author
-
Cutrer FM, Schoenfeld D, Limmroth V, Panahian N, and Moskowitz MA
- Subjects
- Animals, Aorta, Thoracic drug effects, Blood Pressure drug effects, Capsaicin administration & dosage, Cisterna Magna, Depression, Chemical, Guinea Pigs, Heart Rate drug effects, Immunohistochemistry, In Vitro Techniques, Injections, Male, Nociceptors drug effects, Respiratory Mechanics drug effects, Sumatriptan pharmacology, Trigeminal Ganglion cytology, Trigeminal Ganglion drug effects, Capsaicin pharmacology, Proto-Oncogene Proteins c-fos biosynthesis, Pyrrolidines pharmacology, Sumatriptan analogs & derivatives, Trigeminal Ganglion metabolism
- Abstract
1. The effects of an intravenously administered sumatriptan analogue were examined on c-fos-like immunoreactivity (c-fos-LI), a marker of neuronal activation, evoked within trigeminal nucleus caudalis (TNC) and other brain stem regions 2 h after intracisternal injection of the irritant, capsaicin (0.1 ml, 0.1 mM), in pentobarbitone-anaesthetized Hartley guinea-pigs. 2. C-fos-LI was assessed in eighteen serial sections (50 microns) using a polyclonal antiserum. A weighted average, reflecting total expression within lamina I, IIo of TNC was obtained from three representative levels (i.e., at -0.225 mm, -2.475 mm and -6.975 mm.). 3. Capsaicin caused significant labelling within lamina I, IIo, a region containing axonal terminations of small unmyelinated C-fibres, as well as within the nucleus of the solitary tract, area postrema and medial reticular nucleus. A similar distribution of positive cells was reported previously after intracisternal injection of other chemical irritants such as autologous blood or carrageenin. 4. Pretreatment with a conformationally restricted sumatriptan analogue (with some selectivity for 5-HT1B and 5-HTID receptor subtypes) CP-122,288, reduced the weighted average by approximately 50-60% (P < 0.05) in lamina I, IIo at > or = 100 pmol kg-1, i.v., but did not decrease cell number within area postrema, nucleus of the solitary tract or medial reticular nucleus. A similar pattern was reported previously following sumatriptan, dihydroergotamine or CP-93,129 administration after noxious meningeal stimulation. 5. We conclude that modifications at the amino-ethyl side chain of sumatriptan dramatically enhance the suppression of c-fos expression within TNC, a finding consistent with its remarkable potency against neurogenic plasma protein extravasation within dura mater. CP-122,288 and related analogues may serve as an important prototype for drug development in migraine and related headaches.
- Published
- 1995
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.