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 audiogenic seizure-inducing drug H13/04 was found to elicit opposing effects on the in vivo accumulation of 5-HTP (5-hydroxytryptophan) and DOPA (3,4-dihydroxyphenylalanine) in the brain following inhibition of L-amino acid decarboxylase. In strains of mice that normally do not exhibit audiogenic seizures, H13/04 retarded the accumulation of 5-HTP in the telencephalon, diencephalon and brainstem and enhanced the accumulation DOPA in the diencephalon and brainstem. The duration of the biochemical action of H13/04-correlated with the duration of the behavioral effect. When H13/04 is administered to strains of mice with a genetically-determined susceptibility to audiogenic seizures, but at an age when they are developing resistance to seizures, H13/04 does not alter the incidence of sound-induced seizures. The effect on the accumulation of 5-HTP and DOPA was similar to that noted in the genetically-resistant strain; a retardation of the accumulation of 5-HTP in the telencephalon and brainstem and an enhancement of DOPA accumulation in the brainstem. Since the rate of accumulation of 5-HTP and DOPA is a measure of the in vivo rates of tryptophan and tyrosine hydroxylase, respectively, the results may reflect changes in neural activity with consequent effects on the synthesizing enzymes. These results emphasize the usefulness of the drug in analyzing central mechanisms underlying audiogenic seizure activity and in studying functional properties and interactions of the central catechol-and indoleamine systems.
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PMID:Central action of a catechol-amide seizure-inducing agent: opposing effect on tyrosine and tryptophan hydroxylase activity in vivo. 0 34

Six patients with Parkinson's disease developed nocturnal myoclonic attacks after prolongued treatment with L-Dopa which were electroencephalographically recorded. These symptoms persisted after treatment with 2 bromo-alpha-ergocryptin (Bromocryptin), a dopamine receptor agonist, which was substituted for L-Dopa. Bromocryptin is known to have no pre- or postsynaptic effect on serotonin metabolism. It is proposed that these myoclonic phenomena are the expression of the hypersensitivity of denervated catecholamine receptors in the brainstem to the stimulation of L-Dopa and Bromocryptin. This thesis differs with previous suggestions that serotonin plays a major role in the genesis of myoclonic seizures in Parkinsonian patients treated with L-Dopa.
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PMID:Myoclonic attacks induced by L-dopa and bromocryptin in Parkinson patients: a sleep EEG study. 7 16

Seizure development was examined in amygdaloid (AM), hippocampal (HIPP) and septal (SEPT) "KINDLED" CATS BY BEHAVIORAL AND Electrographic methods. hipp seizure developed into motor seizure after establishing secondary epileptogenesis in AM and globys paliidus. A secondary epileptogenesis in the hippocampus was not necessary for AM seizures to develop into generalized conculsions. The SEPT seizure development was almost identical to the hippocampal seizure development. This latter finding suggests that psychomotor epilepsy may not only ne triggered by the HIPP and AM focus but by the septum and its related structures. In the second experiment, the effect of various neuroactive agents on the interictal dischage frequency was studied in AM and HIPP kindled cats. Clear antagonistic action of L-Dopa against reserpine or alpha-MPT induced increase of IID frequency was observed. Viewed in conjunction with our previous assay study of catecholamine that showed a marked depletion of both norepinephrine and dopamine, in hippocampal kindled cat brain, it can be concluded that catecholamine inhibits the establishment and activation of the kindled epileptic neurocircuits.
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PMID:A study of psychomotor epilepsy with "kindled" cat preparations. 13 91

Correlation between the kindled seizure susceptibility and brain monoamine levels was investigated in the hippocampal and amygdaloid kindled cats. Increase of interictal discharge (IID) frequency and morphological change of IID into self-sustained discharge appeared following reserpine administration. alpha-MPT also increased the IID frequency. These changes in reserpine- and alpha-MPT-treated cats were suppressed completely by the administration of L-DOPA, suggesting that depletion of norepinephrine and dopamine exacerbate the kindled seizure susceptibility. In a second experiment, the assay study of brain catecholamine showed significant and parallel depletion of both norepinephrine and dopamine in the hippocampal kindled cat brain. It is concluded that catecholamine may play an inhibitory role in the establishment and neurohumoral control of the kindled seizure susceptibility.
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PMID:[Correlation between seizure susceptibility and brain catecholamine levels. An experimental study using a kindling preparation]. 14 Jun 96

Clinical, electrical and biochemical studies in an eight years old boy with movement-induced seizures were reported. The attack was usually triggered by sudden initiation of movement, but rarely occurred without any apparent movement. Repeated jumping provoked attacks constantly, which was recorded cinematographically. No abnormality was found either in ictal or interictal EEGs. Haloperidol aggravated the condition, but 1-DOPA had no effect, while DPH (100 mg/day) controlled attacks perfectly with the serum DPH concentration of just 2.0 ug/dl. In overnight sleep analysis, sleep rhythms and characters of REM sleep were not differed significantly from the standard. After DPH therapy, stabilization of sleep in general was noticed; that is, total sleep time prolonged, number of sleep stages decreased and interrupting awakening disappeared. Probenecid loading test revealed that 5-HIAA was normal, HVA high, and large amount of octopamine was detected in CSF.
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PMID:Overnight sleep EEG and cerebrospinal fluid monoamines in seizures induced by movement. 22 8

Brain levels of tyrosine, dopamine (DA), noradrenaline (NA), tryptophan, 5-hydroxytryptamine (5-HT), and 5-hydroxyindoleacetic acid (5-HIAA) were measured after 30, 60 and 120 min of sustained seizure activity, induced in paralyzed, artificially ventilated and anaesthetized (70% N2O) rats by administration of bicuculline (1.2 mg/kg i.v.). In separate animals the rates of accumulation of DOPA and 5-hydroxytryptophan (5-HTP) were estimated in three different brain regions after blockage of the aromatic L-amino acid decarboxylase with NSD 1015 (100 mg/kg). The tissue level of NA was markedly reduced at 30 min and remained low during 120 min of sustained epileptic seizures. In contrast, the DA concentration, being essentially unaffected at 30 min, continuously increased during the following 90 min. 5-HT decreased significantly after 30 min but returned to control levels following 60 and 120 min of seizure activity. The 5-HIAA concentration progressively increased. In all three brain regions (striatum, limbic forebrain and hemispheres) the rate of tyrosine hydroxylation increased. Tryptophan hydroxylation showed a significant increase only in the limbic forebrain. The results suggest that bicuculline-induced seizures lead to an increased functional activity in NA neurons and, at least initially, also in 5-HT neurons. In contrast, DA neurons appear to be inhibited.
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PMID:Monoamine metabolism during bicuculline-induced epileptic seizures in the rat. 30 80

Experiments with pentylenetetrazol convulsion model in albino mice--80 mg/kg subcutaneously--have revealed the following. The inhibitory effect of 5-HT, introduced intracerebroventricularly in a dose of 100 micrograms per mouse is eliminated by 500 mg/kg L-DOPA, 100 mg/kg amantadine, 5 mg/kg amphetamine and apomorphine, while for lower doses of the dopaminergic agent only a tendency towards antagonism is observed. The inhibitory effect of 50HTP in a dose of 200 mg/kg i. p. is eliminated by 500 mg/kg L-DOPA, 50 mg/kg amantadine and 5 mg/kg amphetamine, but it is not influenced by these drugs in doses of 250 mg/kg L-DOPA, 25 mg/kg amantadine and 5 mg/kg apomorphine, although when applied independently L-DOPA and amantadine in these lower doses potentiate convulsive reactions. The results obtained show that the dopaminergic and 5-HT-ergic systems have an antagonist effect on the convulsive reactivity in the case of pentylenetetrazol convulsion model. These results are in agreement with our views about the determining role of the balance between the various neurotransmitter systems in convulsive-seizure reactions.
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PMID:On some relationships between dopaminergic and serotoninergic mechanisms in pentylenetetrazol convulsions in albino mice. 31 12

Electrolytic lesions of the median raphe nucleus and substantia nigra markedly increased susceptibility to pentetrazole seizures in rats. L-5-hydroxytryptophan, considerably increasing the serotonin (5-HT) level in the brain, markedly inhibited the seizures and abolished the seizure-enhanced effect of lesion of the substantia nigra. L-DOPA tended to potentiate the seizures-enhancing effect produced by lesions of the median raphe nucleus. The changes in the brain 5-HT level and the intensity of pentetrazole seizures were correlated. The results indicate that the balance between neurotransmitter systems in the brain is of importance to the susceptibility to pentetrazole convulsions.
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PMID:The effect of L-DOPA and L-5-hydroxytryptophan on the pentetrazole seizures in rats after lesions of the median raphe nucleus and substantia nigra. 31 24

In freely moving cats the behavioral and EEG-shifts, accompanied by myoclonic jerks with slow negative waves and spike-wave complexes in the cortexand caudate nucleus, were recorded following a single intramuscular injection of high penicillin doses. The stimulants of catecholaminergic transmission (L-DOPA and apomorphine) inhibited the development of such phenomena but facilitated origination of tonicoclonic cramps. The inhibitors of catecholaminergic synapses (aminazin and haloperidol) exerted reverse effects. The electrolytic injury to the caudate nucleus head also prevented formation of petit mal-like seizures while the threshold low-frequency stimulation of the nucleus increased penicillin effect.
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PMID:[Role of the catecholaminergic mechanisms and of the caudate nucleus in the development of generalized convulsions caused by the parenteral administration of penicillin]. 46 9

The effects of L-DOPA, L-tryptophan, monoamine oxidase inhibitor (MAOI), and MAOI plus L-tryptophan, each for 3 months, have been assessed in 10 severe, adult epileptics with placebo control. There was no overall reduction in seizure frequency, but 2 patients with minor partial seizures improved, 1 with L-DOPA, MAOI, and MAOI plus L-tryptophan, and the other with L-tryptophan and MAOI plus L-tryptophan. We have not been able to demonstrate an increased turnover of cerebral serotonin (5-HT), as measured by cerebrospinal fluid 5-hydroxyindoleacetic acid, after treatment with L-tryptophan for 3 months. This observation casts doubt on the ability of L-tryptophan to alter the long-term metabolism and functional activity of brain 5-HT. The importance of further exploration of manipulation of cerebral monoamines as a possible approach to the treatment of epilepsy is emphasized.
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PMID:Manipulation of cerebral monoamines in the treatment of human epilepsy: a pilot study. 62 66


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