Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0013421 (dystonia)
 8,418 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The novel atypical antipsychotic ziprasidone has a pharmacologic profile notable for potent agonism of serotonin (5-HT)1A receptors, antagonism at 5-HT1D receptors, and reuptake inhibition of norepinephrine. 5-HT1A receptor agonism, in particular, suggests anxiolytic activity, and ziprasidone has shown preliminary efficacy in treating the symptoms of anxiety associated with psychotic disorders. In this study, the anxiolytic efficacy of ziprasidone was evaluated in nonpsychotic subjects who were anxious before undergoing minor dental surgery. We compared a single oral dose of 20 mg ziprasidone (N = 30) with that of 10 mg diazepam (N = 30) and placebo (N = 30) in a randomized, parallel-group, double-blind study. The peak anxiolytic effect of ziprasidone compared with that of placebo was similar to that of diazepam but had a later onset. At 3 hours postdose, the anxiolytic effect of ziprasidone was significantly greater than that of placebo (p < 0.05) and somewhat greater than that of diazepam. Diazepam showed a significantly greater anxiolytic effect than placebo at 1 hour (p < 0.05) but not at 3 hours. The sedative effect of ziprasidone was never greater than that of placebo, whereas that of diazepam was significantly greater than that of placebo 1 to 1.5 hours postdose. Ziprasidone was generally well tolerated. Only one patient reported treatment-related adverse events (nausea and vomiting) and, unlike diazepam, ziprasidone did not cause reductions in blood pressure. Dystonia, extrapyramidal syndrome, akathisia, and postural hypotension were not seen with ziprasidone. Thus, ziprasidone may possess anxiolytic effects in addition to its antipsychotic properties.
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PMID:The anxiolytic effect of the novel antipsychotic ziprasidone compared with diazepam in subjects anxious before dental surgery. 1191 Feb 68

The extensive pharmacological evaluation of JL 13 as an atypical antipsychotic drug has revealed a close similarity to clozapine, however with some major advantages. JL 13 was characterized as a weak D(2) antagonist, both in vitro and in vivo, with a strong affinity for the D(4) and the 5-HT(2A) receptors. It has no affinity for the 5-HT(2C) receptor. In vivo microdialysis experiments in rat showed that JL 13, like clozapine, preferentially increased extracellular dopamine concentrations in the prefrontal cortex compared to nucleus accumbens or striatum. Behavioral studies showed that JL 13, like clozapine, has the profile of an atypical antipsychotic. Thus, JL 13 did not antagonize apomorphine-induced stereotypy nor did it produce catalepsy, but it antagonized apomorphine-induced climbing in rodents. It was inactive against d-amphetamine-induced stereotypy but antagonized d-amphetamine-induced hyperactivity in the mouse. Likewise, in the paw test, it was more effective in prolonging hindlimb retraction time than prolonging forelimb retraction time. Like other antipsychotic drugs, JL 13 reversed the apomorphine- and amphetamine-induced disruption of prepulse inhibition. In a complex temporal regulation schedule in the dog, JL 13 showed a high resemblance with clozapine without inducing sialorrhea, palpebral ptosis or any significant motor side effects. In rats and squirrel monkeys JL 13 induced a high degree of generalization (70%) to clozapine. Regarding behavioral toxicology, JL 13 did not produce dystonia or Parkinsonian symptoms in haloperidol-sensitized monkeys. After acute administration, again like clozapine, JL 13 induced only a transient increase in circulating prolactin. Last but not the least, regarding a possible hematological toxicity, unlike clozapine, JL 13 did not present sensitivity to peroxidase-induced oxidation. Moreover, its electrooxidation potential was close to that of loxapine and far from that of clozapine. Taking all these preclinical data into account, it appears that JL 13 is a promising atypical antipsychotic drug.
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PMID:JL 13, an atypical antipsychotic: a preclinical review. 1259 11

Ecstasy [3,4-methylenedioxymethamphetamine (MDMA)] was shown to prolong the action of L-3,4-dihydroxyphenylalanine (L-DOPA) while suppressing dyskinesia in a single patient with Parkinson's disease (PD). The clinical basis of this effect of MDMA is unknown but may relate to its actions on either dopaminergic or serotoninergic systems in brain. In normal, drug-naive common marmosets, MDMA administration suppressed motor activity and exploratory behavior. In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated, L-DOPA-primed common marmosets, MDMA transiently relieved motor disability but over a period of 60 min worsened motor symptoms. When given in conjunction with L-DOPA, however, MDMA markedly decreased dyskinesia by reducing chorea and to a lesser extent dystonia and decreased locomotor activity to the level observed in normal animals. MDMA similarly alleviated dyskinesia induced by the selective dopamine D2/3 agonist pramipexole. The actions of MDMA appeared to be mediated through 5-HT mechanisms because its effects were fully blocked by the selective serotonin reuptake inhibitor fluvoxamine. Furthermore, the effect of MDMA on L-DOPA-induced motor activity and dyskinesia was partially inhibited by 5-HT1a/b antagonists. The ability of MDMA to inhibit dyskinesia results from its broad spectrum of action on 5-HT systems. Serotoninergic receptors appear to play an important modulatory role in l-DOPA-induced dyskinesia, and this study may provide a framework for the use of serotoninergic agents in the treatment of L-DOPA-induced dyskinesia.
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PMID:3,4-methylenedioxymethamphetamine (ecstasy) inhibits dyskinesia expression and normalizes motor activity in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated primates. 1453 44

Explaining the underlying mechanisms of antipsychotic drug-induced movement disorders remains a substantial challenge. The association of atypical antipsychotic agents with fewer drug-induced movement disorders than conventional agents has engendered several pathophysiologic hypotheses: (1) the hypothesis that, unlike conventional antipsychotic agents, atypical antipsychotics have greater activity in blocking serotonin-2A (5-HT(2A)) receptors than dopamine-2 (D(2)) receptors, which mitigates extrapyramidal symptoms; (2) the hypothesis that atypical antipsychotics block D(2) receptors only long enough to cause an antipsychotic action, but not as long as conventional agents; (3) the hypothesis that, in tardive dyskinesia, the nigrostriatal dopamine receptor system might develop increased sensitivity to dopamine as a result of treatment with conventional antipsychotic drugs, but this may not occur with atypical antipsychotics; and (4) the hypothesis that there might be a genetic association in tardive dystonia relating to the dopamine D(3) allele. A number of factors contribute to the difficult task of gaining insight into the pathophysiologic processes of antipsychotic agents and why these agents may lead to drug-induced movement disorders.
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PMID:Pathophysiology of antipsychotic drug-induced movement disorders. 1518 9

5-Hydroxytryptamine 1a (5-HT(1a)) receptor agonists, such as sarizotan and tandospirone, are reported to reduce levodopa-induced dyskinesia in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated macaques and in Parkinson's disease without worsening motor disability. However, these compounds are not specific for 5-HT(1a) receptors and also possess dopamine antagonist actions. We now report on the effects of (2R)-(+)-8-hydroxy-2-(di-n-propylamino)tetralin [(R)-(+)-8-OHDPAT], a selective 5-HT(1a) agonist lacking dopaminergic activity, on motor disability and dyskinesia (chorea and dystonia) in levodopa-primed MPTP-treated common marmosets. Administration of (R)-(+)-8-OHDPAT (0.2, 0.6, and 2.0 mg/kg s.c), in conjunction with levodopa/carbidopa (12.5 mg/kg each p.o.) to levodopa-primed animals, dose-dependently reduced levodopa-induced chorea but did not affect dystonic movements. However, (R)-(+)-8-OHDPAT treatment also reduced locomotor activity and the reversal of motor disability. Administration of (R)-(+)-8-OHDPAT alone had no effects of motor behaviors. The effects of (R)-(+)-8-OHDPAT on levodopa-induced motor behaviors were antagonized by the 5-HT(1a) receptor antagonist N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-2-pyridinylcyclohexanecarboxamide maleate (WAY-100635) (1.0 mg/kg s.c.). Administration of (R)-(+)-8-OHDPAT (0.6 mg/kg s.c.) also reduced chorea produced by the administration of the D(2)/D(3) dopamine receptor agonist pramipexole (0.06 mg/kg p.o.) to levodopa-primed MPTP-treated animals. However, again the increase in locomotor activity and reversal of motor disability produced by pramipexole were also inhibited. These data suggest that selective 5-HT(1a) agonists do not provide an effective means of suppressing levodopa-induced dyskinesia, except with worsening of parkinsonism.
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PMID:In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated primates, the selective 5-hydroxytryptamine 1a agonist (R)-(+)-8-OHDPAT inhibits levodopa-induced dyskinesia but only with\ increased motor disability. 1695 59

The present study describes the pharmacological profile of the putative antipsychotic drug Lu 35-138 ((+)-(S)-3-{1-[2-(1-acetyl-2,3-dihydro-1H-indol-3-yl)ethyl]-3,6-dihydro-2H-pyridin-4-yl}-6-chloro-1H-indole). The in vitro receptor profile of Lu 35-138 revealed high affinity (K(i)=5 nM) and competitive antagonism (K(b)=8 nM) at dopamine D(4) receptors combined with potent 5-HT uptake inhibition (IC(50)=3.2 nM) and moderate alpha(1)-adrenoceptor affinity (K(i)=45 nM). In vivo, Lu 35-138 selectively counteracted hyperlocomotion induced by d-amphetamine (0.5 mg/kg; ED(50)=4.0 mg/kg, s.c.) in rats and phencyclidine (PCP; 2.5 mg/kg; ED(50)=13 mg/kg, s.c.) in mice. Lu 35-138 was unable to affect hyperlocomotion induced by a high dose of d-amphetamine (2.0 mg/kg), which indicates a preferential action on limbic versus striatal structures. A similar limbic selectivity of Lu 35-138 was indicated in voltammetric measure of dopamine output in the core and shell subdivisions of the nucleus accumbens in rats. Furthermore, a relatively large dose of Lu 35-138 (18 mg/kg, s.c.) counteracted d-amphetamine-induced disruption of pre-pulse inhibition in rats and repeated administration of Lu 35-138 (0.31 or 1.25 mg/kg, p.o. once daily for 3 weeks) reduced the number of spontaneously active dopamine neurones in the ventral tegmental area, underlining its antipsychotic-like profile. Lu 35-138 failed to induce catalepsy in rats or dystonia in Cebus apella monkeys and did not deteriorate spatial memory in rats as assessed by water maze performance. Collectively, these results suggest that Lu 35-138 possesses antipsychotic activity combined with a low extrapyramidal and cognitive side effect liability.
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PMID:Lu 35-138 ((+)-(S)-3-{1-[2-(1-acetyl-2,3-dihydro-1H-indol-3-yl)ethyl]-3,6-dihydro-2H-pyridin-4-yl}-6-chloro-1H-indole), a dopamine D4 receptor antagonist and serotonin reuptake inhibitor: characterisation of its in vitro profile and pre-clinical antipsychotic potential. 1768 29

This paper reviews the main neurological complications of psychiatric drugs, in particular antipsychotics and antidepressants. Extrapyramidal syndromes include acute dystonia, parkinsonism, akathisia, tardive dyskinesia and tardive dystonia. Extrapyramidal symptoms (EPS) are less frequent with atypical than with conventional antipsychotics but remain common in clinical practice partly due to lack of screening by health professionals. Neuroleptic malignant syndrome (NMS) consists of severe muscle rigidity, pyrexia, change in conscious level and autonomic disturbance but partial forms also occur. NMS is particularly associated with the initiation and rapid increase in dose of high-potency antipsychotics but it has been reported with all the atypical antipsychotics and rarely with other drugs including antidepressants. Serotonin toxicity comprises altered mental state (agitation, excitement, confusion), neuromuscular hyperactivity (tremor, clonus, myoclonus, hyper-reflexia) and autonomic hyperactivity and occurs on a spectrum. Severe cases, termed serotonin syndrome, usually follow the co-prescription of drugs that increase serotonergic transmission by different pathways, for example a monoamine oxidase inhibitor (MAOI) and a selective serotonin reuptake inhibitor (SSRI). Most antipsychotics and antidepressants lower the seizure threshold and can cause seizures; the risk is greater with clozapine than with other atypical antipsychotics and greater with tricyclic antidepressants (TCAs) than with SSRIs. In randomised controlled trials in elderly patients with dementia atypical antipsychotics are associated with a higher risk of stroke and death than placebo. Cohort studies suggest that conventional drugs carry at least the same risk. Cessation of treatment with antipsychotics and antidepressants can lead to a wide range of discontinuation symptoms which include movement disorders and other neurological symptoms. Clinicians need to be familiar with strategies to reduce the risk of these adverse events and to manage them when they arise. Their occurrence needs to be balanced against the benefits of psychiatric drugs in terms of efficacy and improved quality of life in a range of disorders.
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PMID:Neurological complications of psychiatric drugs: clinical features and management. 1809 17

Serotonin-selective re-uptake inhibitors are prescribed widely because they are regarded as having less severe side-effects compared with tricyclics and monoamine oxidase inhibitors. With this popularity, increasing attention has been drawn to their adverse effects. Development of extrapyramidal symptoms has been reported in some patients while taking fluoxetine, a commonly used serotonin-selective re-uptake inhibitor. Here, we report a case of persistent dystonia, thought to be associated with short-term fluoxetine use, which required treatment with botulinum toxin type A.
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PMID:Persistent dystonia induced by fluoxetine. 1880 63

Typical antipsychotics such as haloperidol exert their therapeutic effects via blockade of dopamine (DA) D(2) receptors, leading to extrapyramidal symptoms (EPS) in humans and catalepsy in rodents. In contrast, atypical antipsychotics and new generation D(2)/5-HT(1A) antipsychotics have low cataleptogenic potential. However, there has been no systematic comparative study on the effects of these different classes of antipsychotics in non-human primates, a species displaying a more sophisticated repertoire of behavioural/motor activity than rats. Once weekly, six young adult female non-haloperidol-sensitised cynomolgus monkeys were treated i.m. with a test compound and videotaped to score catalepsy-associated behaviour (CAB: static postures, unusual positions and crouching). Haloperidol, risperidone, olanzapine, nemonapride and remoxipride induced, to different extents, an increase in unusual positions (a response akin to dystonia), some crouching and static postures. In contrast, clozapine, quetiapine, ziprasidone and aripiprazole produced much lower or no unusual positions; clozapine also produced marked increases in static postures and crouching. Among novel D(2)/5-HT(1A) antipsychotics, SLV313 and F15063 augmented the number of unusual positions, albeit at doses 16-63 times higher than those of haloperidol for approximately the same score. SSR181507 and bifeprunox produced moderate static postures, little crouching and negligible unusual positions. These data provide the first comparative analysis in cynomolgus monkeys of EPS liability of conventional, atypical and novel D(2)/5-HT(1A) antipsychotics. They indicate that the latter are less prone than haloperidol to produce CAB, and provide a basis for comparison with rodent catalepsy studies.
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PMID:Differences among conventional, atypical and novel putative D(2)/5-HT(1A) antipsychotics on catalepsy-associated behaviour in cynomolgus monkeys. 1946 24

Dystonia is an involuntary movement disorder characterized by repetitive patterned or sustained muscle contractions causing twisting or abnormal postures. Several lines of evidence suggest that abnormalities of dopaminergic pathways contribute to the pathophysiology of dystonia. In particular, dysfunction of D2-like receptors that mediate function of the indirect pathway in the basal ganglia may play a key role. We have demonstrated with positron emission tomography that patients with primary focal cranial or hand dystonia have reduced putamenal specific binding of [(18)F]spiperone, a nonselective D2-like radioligand with nearly equal affinity for serotonergic 5-HT(2A) sites. We then repeated the study with [(18)F]N-methyl-benperidol (NMB), a more selective D2-like receptor radioligand with minimal affinity for 5-HT(2A). Surprisingly, there was no decrease in NMB binding in the putamen of subjects with dystonia. Our findings excluded reductions of putamenal uptake greater than 20% with 95% confidence intervals. The analysis of the in vitro selectivity of NMB and spiperone demonstrated that NMB was highly selective for D2 receptors relative to D3 receptors (200-fold difference in affinity), whereas spiperone has similar affinity for all three of the D2-like receptor subtypes. These findings when coupled with other literature suggest that a defect in D3, rather than D2, receptor expression may be associated with primary focal dystonia.
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PMID:Decreased striatal dopamine receptor binding in primary focal dystonia: a D2 or D3 defect? 2096 Apr 37


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