Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The concentrations of homovanillic acid and 5-hydroxyindoleacetic acid were determined in the cerebrospinal fluid in 17 patients with Parkinson's disease and 10 controls. The patients with Parkinson's disease were on long-term treatment with L-DOPA preparations. In 9 of them drug-induced dyskineses were observed. The HVA/5-HIAA ratio was determined in the cerebrospinal fluid separately in cases with dyskineses, in cases without dyskineses and in controls. It was found that this ratio was significantly higher in patients with drug-induced dyskineses as compared to patients without dyskineses, and especially to controls. It is suggested that this may mean that in cases of drug-induced dyskineses disturbances exist in the equilibrium between the dopaminergic and serotoninergic systems in favour of the former, which may be one of the causes of involuntary movements.
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PMID:[Drug-induced dyskinesia during the treatment of Parkinson disease--biochemical studies]. 242 Nov 91

Idiopathic Parkinson's Disease arises from the progressive loss of dopamine (DA)-utilizing neurons of the nigrostriatum and responds to the replacement of DA with L-dihydroxyphenylalanine (L-DOPA). In awake rats, with unilateral lesions induced with 6-hydroxydopamine (6-OHDA) of the DA-utilizing nigrostriatal pathway, treatment with L-DOPA causes the rapid onset of brisk contralateral turning behaviour. In urethane-anesthetized rats with identical unilateral lesions of the nigrostriatum, dialysis of the striatum, performed before and after the systemic administration of L-DOPA (25 mg/kg i.p.), did not demonstrate any alteration in extracellular DA in the striatum which was DA-deprived compared to intact striata. After treatment with L-DOPA extracellular levels of the metabolites of DA. DOPAC and HVA increased several fold. These results suggest: (a) DA neurons surviving after extensive lesions with 6-OHDA can compensate for loss of DA in the striatum and maintain extracellular fluid (and presumably synaptic) concentrations of DA; (b) in striata with extensive depletion of DA L-DOPA undergoes rapid decarboxylation to DA, followed by catabolism to DOPAC and HVA; and (c) in urethane-anesthetized animals, DA formed from DOPA does not appear to enter a releasable pool.
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PMID:The metabolism of systemically-administered L-dihydroxyphenylalanine, by intact and dopamine-denervated striata, as revealed by brain microdialysis. 259 66

Systemic exposure to the neurotoxin MPTP produces a Parkinsonian syndrome in man and primates, but not in adult rats. However, embryonic rat dopamine neurons in cell cultures are selectively destroyed by MPTP. This study examined whether similar effects on dopamine neurons occur in vivo, by studying dopamine-mediated behaviors in rats prenatally treated with MPTP or its active metabolite MPP+. Pregnant rats were injected daily with MPTP, MPP+, or vehicle from gestational day (E)13 until birth. There were time-dependent increases in spontaneous locomotor and rearing activity. Offspring of both the MPTP and MPP+ groups were hyporesponsive to d-amphetamine (1 mg/kg IP) at postnatal day 21. This hyporesponsiveness persisted at postnatal day 50 in the pups from MPTP-treated mothers. However, the striatal concentration of dopamine and its metabolites DOPAC and HVA were not significantly affected by the prenatal MPTP or MPP+ treatments. Both MPTP and MPP+ groups had significantly increased stereotypic responses to apomorphine (0.2 mg/kg SC) on both postnatal days 21 and 50. These results demonstrated persistent postsynaptic supersensitivity to dopaminergic agonists following prenatal MPTP/MPP+ treatment. That fetal rats develop long-term sequelae after prenatal exposure to MPTP/MPP+ suggests a different sensitivity of the immature rat dopamine neurons than in adult rats. Understanding this difference may provide useful information in the development of animal models of Parkinson's Disease.
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PMID:The effect of prenatal treatment with MPTP or MPP+ on the development of dopamine-mediated behaviors in rats. 262 12

The characteristics of motor function and brain dopamine (DA) metabolism in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice after immersion immobilization stress were investigated. There was no significant difference in locomotor activities between MPTP-treated and saline-treated mice, but locomotor activities of MPTP-treated mice after stress decreased more remarkably than those of saline-treated mice. Immediately after stress, striatal DA concentrations of MPTP-treated mice were significantly lower than those of saline-treated mice. Striatal DA levels improved when 24 h passed after stress. The striatal and cortical (DOPAC + HVA)/DA ratios of MPTP-and stress-treated mice was significantly higher than that of saline-and stress-treated mice. It is due to the decreased DA level and the enhancement of DA turnover that MPTP-treated mice became remarkably akinetic after stress, and that L-DOPA therapy is not effective when the symptoms in patients with Parkinson's disease worsen due to stress.
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PMID:Increase of striatal dopamine turnover by stress in MPTP-treated mice. 326 55

A procedure is described for the rapid determination of the major indoles and catechols. Analysis with picogram detection limits was done by high-pressure liquid chromatography on a C18 reverse-phase column using electrochemical detection (LCEC). This method provides a comprehensive list of compounds which can be simultaneously determined in brain samples and for which there is no necessity of derivatization or pre-column purification. The regional distribution of 9 neurochemicals from rat brain and the levels of 10 neurochemicals from human brain are presented. DOPA, TYR, NE, MHPG, DOPAC, 5-HIAA, TRP, DA, HVA, 3-MT and 5-HT were detected in the caudate nucleus and putamen. The levels of neurochemicals from the caudate and putamen of a demented patient with Parkinson's disease were variably decreased; catechol and indole losses were greatest in the putamen. The levels of neurochemicals in the caudate and putamen of patients with Alzheimer's disease (SDAT) were also variably decreased; loss of NE was seen only in putamen and losses of DA, HVA and 5-HT were uniform across both caudate and putamen. The CSF of SDAT patients showed changes in NE only.
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PMID:Determination of tyrosine, tryptophan and their metabolic derivatives by liquid chromatography-electrochemical detection: application to post mortem samples from patients with Parkinson's and Alzheimer's disease. 396 72

The amine metabolites HVA and 5-HIAA in the lumbar CSF of 15 patients with Huntington's chorea were determined. A negative correlation was found between the severity of symptoms and the CSF HVA, but not 5-HIAA levels. The mean HVA concentration was lower than that of a group of patients with miscellaneous neurological disorders, similar to that of a group with miscellaneous psychiatric disorders and higher than that of a group with Parkinson's disease. The mean 5-HIAA concentration was similar to that of the neurological group and higher than those of the groups with psychiatric disorders or Parkinson's disease. CSF HVA and 5-HIAA concentrations of a single patient with severe akinetic rigid Huntington's chorea were similar to those found in Parkinson's disease. The findings are discussed in relation to previous neuropathological observations and to reported effects of drugs on the choreic symptoms.
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PMID:Amine metabolites in the cerbrospinal fluid in Huntington's chorea. 426 57

The 5-HIAA/HVA ratio was determined in the cerebrospinal fluid in 5 patients with Parkinson's disease with L-DOPA preparations in which drug-induced dyskineses developed, in 5 patients treated with L-DOPA without dyskineses, and 10 controls. A decrease in the 5-HIAA/HVA ratio was observed in the group with dyskineses as compared with patients without dyskineses and in controls. The directions of further investigations on hte pathomechanism of drug-induced dyskineses are discussed.
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PMID:[Pathomechanism of dyskinesia associated with treatment of Parkinson disease with levodopa]. 617 92

Iron has recently been suggested to contribute to the pathogenesis of Parkinson's disease (PD) because of the finding of increased iron levels in the substantia nigra pars compacta (SNc) above those of control patients. Iron is capable of catalyzing numerous reactions which could lead to free radical formation and oxidative damage to DNA, proteins, lipid membranes, and other biological molecules. Neurodegeneration in the SNc of the PD brain may be a consequence of increased iron, which promotes these cytotoxic reactions. To test whether excess iron could play a causative role in the degeneration of nigral neurons, we infused 1.25-6.3 nmol of iron into the rat substantia nigra (SN) unilaterally utilizing two different infusion protocols. All infusates were isosmotic and pH-balanced in a citrate-bicarbonate vehicle. Animals were decapitated at either 1 or 2 months postinfusion. Striatal tissue was assayed for biogenic amines by HPLC and the remaining brainstem was processed for histological analysis. Iron-stained coronal sections revealed 1) no left/right staining difference with vehicle infusion, 2) a dose-dependent iron accumulation in the infused SN that was restricted to the zona compacta and dorsal-most zona reticularis when the lowest iron concentration was infused, and 3) a dose-dependent reduction in SN volume. Thionine-stained sections revealed neuronal loss and accompanying reactive gliosis within an area that corresponded closely to that of increased iron staining. These degenerative changes were more extensive in animals infused via a side-by side vs. a sequential protocol. Neurochemically, there was a highly significant correlation between the amount of iron infused intranigrally and magnitude of reductions in striatal DA, DOPAC, and HVA within the ipsilateral striatum. These data indicate that iron infusion into the SN can cause degenerative changes within the SN and that these changes can be restricted to the SNc region when low amounts of iron are infused. The data further support the hypothesis that iron-induced degeneration may contribute to the pathogenesis of PD.
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PMID:Infusion of iron into the rat substantia nigra: nigral pathology and dose-dependent loss of striatal dopaminergic markers. 768 99

A course of treatments with electroconvulsive shock (ECS) has been reported to reestablish L-dopa efficacy in patients with advanced Parkinson's disease. We wished to determine if ECS could modify L-dopa and dopamine metabolism in an animal model of Parkinson's disease. Therefore, we administered repeated ECS (8 ECS at 48 hr intervals) to rats with partial destruction of the nigrostriatal dopamine pathway and used the cerebral microdialysis technique to monitor extracellular concentrations of dopamine and dopamine metabolites (DOPAC and HVA) in the corpus striatum. The control group of animals received sham-ECS treatments. Basal dopamine levels were decreased by 20% in animals receiving repeated-ECS versus sham-ECS. DOPAC levels, on the other hand, were increased by 84% in animals receiving repeated-ECS. HVA levels were equal in the two groups. Following L-dopa administration, dopamine and HVA levels increased equally in control animals and animals which had previously received repeated-ECS. DOPAC concentrations were uniformly greater in rats receiving repeated-ECS. When ECS was administered acutely, dopamine levels increased 390% and returned to baseline values in 75 minutes, DOPAC and HVA were unchanged, and 5HIAA levels decreased 30%. We conclude that 1) acute ECS administration produces a transient, marked release of striatal dopamine and 2) repeated ECS can reset the level of basal dopamine release, a finding compatible with ECS-induced dopamine receptor supersensitivity, and 3) neither single nor repeated administration of ECS has a major effect on the formation of dopamine or HVA from exogenously administered L-dopa although there was a strong tendency for increased DOPAC formation. ECS may exert its putative antiparkinsonian effect by enhancing dopamine receptor sensitivity.
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PMID:Effect of repeated electroconvulsive shock on striatal L-dopa and dopamine metabolism: an in vivo study. 769 72

We have developed two HPLC systems for the simultaneous determination of CA, 5-HT and their precursors and metabolites in human body fluid. One system consisted of two reversed-phase columns, a column switching device, a pair of electrodes for elimination of interferents and two sets of new electrochemical detectors with four electrodes. Using this system, adequate separation of peaks for 17 kinds of CA, 5-HT and their related metabolites in a standard solution required only 17 min. NE, MHPG, DOPAC, 5-HIAA, HVA and TRP levels in cerebrospinal fluid (CSF) were determined without any pretreatment of the CSF samples. The concentrations of DOPAC, 5-HIAA and HVA in CSF were significantly lower in Alzheimer's disease, vascular dementia and Parkinson's disease than in the controls. The other system was developed for determination of CA acidic metabolites and 5-HIAA in human urine. This system consisted of a mixed-mode column (C18/anion) and 8-channel electrochemical detector with isocratic elution of citrate buffer. Detection limits, precision and analytical recoveries of this method were satisfactory for clinical use.
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PMID:[Simultaneous determination of catecholamines, serotonin, and their precursors and metabolites in body fluid by an HPLC system with multi-electrode electrochemical detector]. 791 40


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