Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chronic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induced parkinsonian symptoms, predominantly bradykinesia and tremor, in marmosets. These symptoms were reduced by L-DOPA plus benserazide but the putative D1-receptor agonist SKF 38393-A did not affect tremor and increased the bradykinesia. Neither treatment affected behaviour in normal marmosets. It is suggested that D1-receptor agonists are unlikely to be effective in the treatment of Parkinson's disease.
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PMID:Failure of SKF 38393-A to relieve parkinsonian symptoms induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in the marmoset. 392 7

The administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) (1-4 mg/kg i.p.) for 4 days induced dose-dependent parkinsonism in the common marmoset within 48 h. MPTP produced profound akinesia, rigidity of the trunk and limbs, postural abnormalities, loss of vocalization and, in some cases, postural tremor. In a single animal the administration of L-DOPA in conjunction with a peripheral decarboxylase inhibitor, reversed the parkinsonian symptoms. Subsequent biochemical analysis showed a profound loss of dopamine and [3H]dopamine uptake in the caudate-putamen, but no change in specific [3H]spiperone binding.
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PMID:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced parkinsonism in the common marmoset. 643 58

Application of the common marmoset to pharmacological studies was reviewed, especially employment of the animal as a model of Parkinson's disease were presented. The common marmoset is one of the New World monkeys with a body weight of 300-350 g. It is small enough to be easily handled and to be kept as a group in a room. In the fields of pharmacology, it has been used in studies of plasma renin activity inhibitors, lipoprotein, memory/learning, obstetrics, transplantation, toxicology, anxiolytic agents and virology/immunology. We showed that the common marmoset was a useful animal for studies on Parkinson's disease, dopamine metabolism by microdialysis and nausea/vomiting. The common marmoset was sensitive to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and developed permanent parkinsonism after MPTP injection. MPTP-treated common marmosets showed tremor and akinesia, and it remarkably responded to antiparkinsonian agents. A dopamine D1 agonist, which caused stereotyped behavior in rats, did not reverse parkinsonism in humans. We showed this agent did not have any antiparkinsonian effects on MPTP-treated common marmosets. MAO has subtypes, A and B, that have differences of distribution in different species. MAO type B inhibitors were applied for the treatment of Parkinson's disease. MAO subtype B inhibitors do not cause any change in behavior or extracellular concentration of dopamine or its metabolites in rodents. In MPTP-treated common marmosets, however, administration of a MAO type B inhibitor increased the antiparkinsonian effects of levodopa and decreased dopamine metabolites. The common marmoset is a suitable animal for the study of MAO type B inhibitors.
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PMID:[Application of the common marmoset to pharmacological studies]. 759 May 19

We have previously demonstrated that chronic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) infusion to the substantia nigra (SN) and the locus coeruleus (LC) both produce a long-lasting neurotoxicity on dopamine (DA) and norepinephrine (NE) neurons in these two areas, respectively. In the present study, we further examined the toxicity of MPTP in these two areas by using the immunohistochemical method. We have also assessed the role of glia cells in the SN and LC in mediating the toxicity of MPTP. Immunohistochemical results have confirmed the direct toxicity of MPTP in the SN, as revealed by significant decreases of tyrosine hydroxylase (TH)-positive cells in the SN and TH-positive fibers in the striatum. The specific gliotoxin alpha-aminoadipic acid (alpha-AA), when administered to the SN at 48 h interval, partially antagonized DA depletions and behavioral deficits produced by chronic MPTP treatment. When alpha-AA was administered to the SN every 24 h, it completely abolished the toxicity of MPTP. On the other hand, chronic MPTP infusions to the LC significantly decreased DA-beta-hydroxylase-positive cells in this area. When alpha-AA was injected into the LC at 48 h intervals, it did not prevent depletions of NE in the LC and the hippocampus caused by chronic MPTP infusions. It did not protect against the behavioral deficits produced by MPTP, either. When alpha-AA was injected into the LC every 24 h, it only partially prevented the toxicity of MPTP on NE in the LC. It also partially prevented the motor-impairing effect of MPTP; however, it barely protected against MPTP's toxicity on NE in the hippocampus and it did not antagonize the stereotypy deficit produced by chronic MPTP, either. Phasic tremor and rigidity were observed following MPTP infusions to the SN and the LC every day, but these symptoms were less frequently observed during the later experimental stage. Serotonin measures were not significantly altered by these treatments throughout these experiments. Immunoblotting results of glial fibrillary acidic protein (GFAP), a marker protein of astrocytes, have confirmed proper lesions of astrocytes by alpha-AA. These results together suggest that chronic MPTP treatment exerts a direct and long-lasting toxicity on DA neurons along the nigrostriatal pathway and NE neurons along the coeruleus-hippocampal pathway. The neurotoxicity of MPTP is probably mediated through astrocytes in the SN, and may be partly mediated through astrocytes in the LC also. These results imply a role for dendritic uptake of DA and NE in these cell body regions. However, these findings also suggest the possibility of differential mechanisms of MPTP's toxicity in these two areas.
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PMID:Differential interactive effects of gliotoxin and MPTP in the substantia nigra and the locus coeruleus in BALB/c mice. 768 60

The main clinical features, pathophysiology and underlying mechanisms of drug-induced parkinsonism are reviewed. The clinical manifestations of drug-induced parkinsonism are often indistinguishable from idiopathic Parkinson's disease. However, some subtle differences may exist: for example drug-induced parkinsonism is often associated with tardive dyskinesias, bilateral symptoms and the absence of resting tremor, etc. Besides toxins (eg manganese, carbon monoxide or MPTP), many drugs are known to produce parkinsonism: dopamine blocking drugs (true neuroleptics used as antipsychotics: phenothiazines, butyrophenones, thioxanthenes but also sulpiride, "hidden" neuroleptics prescribed as anti-nausea or anti-vomiting drugs (such as metoclopramide and other benzamide derivatives), dopamine depleting drugs (reserpine, tetrabenazine), alpha-methyldopa, calcium channel blockers (flunarizine, cinnarizine, etc). The putative role of other drugs (eg fluoxetine, lithium, amiodarone) as well as the therapeutic management of this side effect are reviewed.
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PMID:Drug-induced parkinsonism: a review. 785 36

1. The neuronal mechanisms underlying the major motor signs of Parkinson's disease were studied in the basal ganglia of parkinsonian monkeys. Three African green monkeys were systemically treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) until parkinsonian signs, including akinesia, rigidity, and a prominent 4- to 8-Hz tremor, appeared. The activity of neurons in the subthalamic nucleus (STN) and in the internal segment of the globus pallidus (GPi) was recorded before (STN, n = 220 cells; GPi, n = 175 cells) and after MPTP treatment (STN, n = 326 cells; GPi, n = 154 cells). 2. In STN the spontaneous firing rate was significantly increased from 19 +/- 10 (SD) spikes/s before to 26 +/- 15 spikes/s after MPTP treatment. Division of STN neurons recorded after MPTP treatment into cells with rhythmic bursts of discharge occurring at 4-8 Hz (as defined by autocorrelation analysis) and neurons without 4- to 8-Hz periodic activity revealed an even more prominent increase in the firing rate of the 4- to 8-Hz oscillatory neurons. 3. In GPi overall changes in the average firing rate of cells were inconsistent between different animals and behavioral states. However, the average firing rate of the subpopulation of neurons with 4- to 8-Hz periodic oscillatory activity after treatment with MPTP was significantly increased over that of all neurons before MPTP treatment (from 53 to 76 spikes/s, averaged across monkeys). 4. In the normal state the percentage of neurons with burst discharges (as defined by autocorrelation analysis) was 69% and 78% in STN and GPi, respectively. After MPTP treatment the percentage of cells that discharged in bursts was increased to 79% and 89%, respectively. At the same time the average burst duration decreased (from 121 +/- 98 to 81 +/- 99 ms in STN and from 213 +/- 120 to 146 +/- 134 ms in GPi) with no significant change in the average number of spikes per burst. 5. Periodic oscillatory neuronal activity at low frequency, highly correlated with tremor, was detected in a large number of cells in STN and GPi after MPTP treatment (average oscillation frequency 6.0 and 5.1 Hz, respectively). The autocorrelograms of spike trains of these neurons confirm that the periodic oscillatory activity was very stable. The percentage of cells with 4- to 8-Hz periodic activity significantly increased from 2% to 16% in STN and from 0.6% to 25% in GPi with the MPTP treatment.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The primate subthalamic nucleus. II. Neuronal activity in the MPTP model of parkinsonism. 798 15

1. The effects of reversible and irreversible pharmacological manipulations of the neuronal activity in the subthalamic nucleus (STN) on parkinsonian motor signs and neuronal activity in the internal segment of the globus pallidus (GPi) were studied in African green monkeys rendered parkinsonian by treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. 2. Muscimol injections (< or = 1 microliter, 1 microgram/microliter) into STN reduced neuronal activity recorded at the injection site within minutes. This was immediately followed by reduced akinesia, tremor, and rigidity, as well as the emergence of dyskinesias in contralateral limbs. The motor effects were accompanied by generalized behavioral activation, lasted between 10 and 60 min, and were strongly dependent on the site of injection, with injections into the lateral "arm area" of STN first affecting contralateral arm movements and injections into the "leg" area affecting leg movements first. 3. Bicuculline injections (< or = 1 microliter, 1 microgram/microliter) into STN marginally increased the neuronal activity and induced neuronal discharge in bursts. Rigidity, akinesia, and tremor in the contralateral limbs were not changed. 4. Injections of ibotenic acid in two animals (2 and 7 microliters, 10 micrograms/microliters) resulted in 70 and 51% destruction of STN, respectively. Similarly to the muscimol injections, this resulted in a reduction of the neuronal activity, a reversal of parkinsonian motor signs, and the development of dyskinesias in the contralateral limbs. 5. Although tremor was significantly reduced after STN lesions, periodic oscillatory neuronal activity in GPi persisted. The strength of modulation of the neuronal oscillation was not significantly changed after STN lesion. 6. The percentage of cells in GPi exhibiting increases in discharge in response to torque application was significantly reduced after STN lesion. The magnitude and duration of the responses with increase in firing rate were reduced after STN lesioning. 7. These results support the hypothesis that abnormally increased tonic and phasic activity in STN leads to abnormal GPi activity and is a major factor in the development of parkinsonian motor signs. Furthermore they imply that cells in the basal ganglia have the intrinsic property of discharging in periodic bursts, which is unmasked under parkinsonian conditions.
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PMID:The primate subthalamic nucleus. III. Changes in motor behavior and neuronal activity in the internal pallidum induced by subthalamic inactivation in the MPTP model of parkinsonism. 798 16

An experimental parkinsonian syndrome (PS) was induced by systemic administration of MPTP or oxotremorine, by intranigral administration of MPP+ or injection of acetyl choline and proserine into the rostral part of both caudate nuclei. The development of extrapyramidal disorders was studied simultaneously with EEG recording. The electric activity (EA) was recorded in the sensorimotor cortex, caudate nuclei, ventrolateral nuclei of the thalami, substantia nigra and globus pallidus. Tremor, oligokinesia and rigidity were characterized by the appearance of paroxysmal activity on EA with high amplitude of slow and rapid waves. The data obtained allow us to conclude that PS neuropathophysiological basis is the formation of the generator of pathologically enhanced excitation (GPEE) in the caudate nuclei. It was found that akinesia-rigidity syndromes were observed in the rats with both MPTP and MPP(+)-induced PS. Tremor was observed after administration of oxotremorine or acetyl choline with proserine more often than after treatment with MPTP or MPP+. Some peculiarities of the GPEE activity in these forms of PS were observed. Also, there is dissociation in effects of antiparkinsonian drugs in different forms of PS.
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PMID:[The characteristics of a parkinsonian syndrome induced in an experiment by a deficiency of nigrostriatal dopamine and by stimulation of the cholinergic neurons of the caudate nucleus]. 816 Apr 97

A number of neurodegenerative diseases can manifest as parkinsonian disorders. Structural imaging, such as CT and MRI, is of limited value for differentiating these diseases. PET can demonstrate the selective patterns of disruption of regional cerebral metabolism and neurotransmitter systems associated with subcortical degenerations, such as Parkinson's disease, striatonigral degeneration, progressive supranuclear palsy, and corticobasal degeneration. It can also determine, where underlying Parkinson's disease may be suspected, whether nigral dysfunction is present in patients with isolated tremor or drug-associated rigidity. Finally, PET can detect the presence of subclinical disruption of the dopaminergic system in at-risk subjects, such as relatives of patients with Parkinson's disease, or subjects exposed to nigral toxins, such as MPTP. With the advent of putative neuroprotective agents for Parkinson's disease, PET can help identify patients with early disease who might benefit from therapy with these agents and monitor their disease progression.
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PMID:PET studies on the early and differential diagnosis of Parkinson's disease. 826 13

This article focuses on the current knowledge about movement disorders associated with alcohol and drug abuse. Chronic alcohol use can produce a wide spectrum of movement disorders including tremor, withdrawal parkinsonism and dyskinesias, cerebellar ataxia, and asterixis. MPTP, a neurotoxin first reported to cause parkinsonism in a group of drug abusers, has provided important insights into the pathogenesis of Parkinson's disease. There is a growing body of literature providing evidence that dyskinesias such as tics and dystonia may be precipitated or exacerbated by cocaine. Amphetamines have been implicated in the production of stereotypies and exacerbation of tics.
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PMID:Movement disorders. 837 47


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