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1.
Dyskinesias commonly appear during L-dihydroxyphenylalanine (L-DOPA) therapy of advanced Parkinson's disease (PD) and can occur in both dose-related and dose-independent patterns. Clozapine exerts a dose-related suppression of L-DOPA-induced dyskinesias by shifting the i.v. L-DOPA dose-response curve for production of dyskinesias without altering relief of parkinsonism. We report our outpatient experience with 13 patients on daily clozapine therapy (maximum dose 400 mg/day), followed for 3-21 months (median 10). Beneficial effects of clozapine, determined from twice-weekly diaries, included increased "on time" and decreased "off time" and time "on with dyskinesia." Improvements were statistically apparent by 75 mg/day and remained so through 200 mg/day. Sedation was a common problem, reflected by increased time "asleep" which was significant by 50 mg/day. Sedation was dose limiting in most patients. Orthostatic hypotension and sialorrhea were variably present. No patients had seizures, bone marrow toxicity, or detectable loss of efficacy of clozapine with chronic use. We conclude that clozapine is an effective agent for suppression of dyskinesias in PD with an effective daily dose for most patients of 100-200 mg/day.  相似文献   

2.
Recent advances in magnetic resonance spectroscopy(MRS) allow to assay noninvasively key molecules of brain metabolism in living patients. There are several reports of MRS in Parkinson's disease(PD) and multiple system atrophy(MSA). 1H-MRS of the striatum revealed the reduced NAA/Cr and Cho/Cr ratio in MSA patients and the preserved NAA/Cr and Cho/Cr ratio in PD patients. The reduced NAA/Cr ratio probably reflects striatal neuronal loss. 1H-MRS of the striatum showed increased Cho/Cr ratio in the "on" state compared with that in the "off" state in the PD patients. The increased Cho/Cr ratio may reflect some membrane alteration or change of choline metabolism in PD with the "wearing-off" phenomena. Although studies are still preliminary, MRS shows great possibility for aiding in the differential diagnosis of parkinsonism and it will contribute to a better understanding of the pathogenesis of PD and MSA.  相似文献   

3.
Event-related synchronization (ERS) after self-paced, voluntary brisk movement of the right and left thumb was studied in 17 patients with Parkinson's disease (PD) and 17 age-matched control subjects. All patients were receiving L-DOPA and/or DOPA-agonists. The movement-offset-triggered EEG data were analyzed in the 12- to 16-Hz, 16- to 20-Hz, and 20- to 24-Hz bands for eight time intervals after termination of movement. Significant differences in postmovement beta synchronization were observed in all three frequency bands. As compared with the control group, patients with PD showed a remarkably smaller beta ERS. This was the overall main effect for groups, as well as for interactions concerning side of movement and electrode positions. If beta ERS is a measure of recovery of the primary motor area after movement, our results indicate that this ability is impaired in PD patients.  相似文献   

4.
In an open label study 63 patients with idiopathic Parkinson's disease suffering from end-of-dose akinesia were switched from a treatment with a L-DOPA standard formulation to a combined therapy of L-DOPA standard in the morning and L-DOPA slow release (levodopa, benserazide, Madopar Depot) at the remaining single doses. Substitution of L-DOPA standard by L-DOPA slow release took on average 2-4 weeks. Patients were subsequently treated for 6 months. Due to a lower bioavailability of the slow release formulation--the latter is based on the "hydrodynamically balanced system" (HBS)--, the patients remained initially on their time schedule of drug intake but received a higher dose of L-DOPA slow release compared to the preceding L-DOPA standard therapy. In 20 centers 37 men and 26 women were included into the study. 27 males and 20 females completed the 6 month treatment period. Before switching, the patients received 438 +/- 213 mg a day L-DOPA standard, after conversion, the average dose was 617 +/- 323 mg L-DOPA slow release and 107 +/- 95 mg L-DOPA standard a day. Fluctuations during the day and at night which were rated according to a newly developed clinical 5-point rating scale were significantly improved by the treatment regimen from 2.8 +/- 0.9 to 1.4 +/- 1.2. Additionally, parkinsonian symptoms were significantly reduced during the ON-phase as there was a significant decrease of the Webster rating score from 12.0 +/- 4.6 to 7.1 +/- 4.0. Quality of life as measured by subjective ratings of the patients improved. The tolerability of the new formulation of L-DOPA was rated to be good in 51.1% and very good in 48.9%. The results of this open label study suggest that the combination of L-DOPA standard in the morning and L-DOPA slow release formulation at the following time points can be an efficient therapy in parkinsonian patients who suffer form L-DOPA related end-of-dose motor akinesia.  相似文献   

5.
We report the results of clinical and polysomnographic investigations on 39 consecutive multiple system atrophy (MSA) patients. Twenty-seven patients (69%) reported nocturnal motor paroxysmal episodes related to dreams, suggesting the clinical diagnosis of REM sleep behavior disorder (RBD). In 12 of them (44%), RBD preceded the clinical onset of the disease by more than 1 year. In seven (26%), the RBD onset was concomitant with and in eight (30%) was at least 2 years after the appearance of motor or autonomic symptoms. On polysomnographic recordings, 35 of 39 MSA patients (90%) had RBD. Other polysomnographic findings included nonclinical obstructive sleep apnea in 6 patients, laryngeal stridor in 8 patients, and periodic limb movements during sleep in 10 patients. Our data show that RBD represents the most common clinical sleep manifestation and polysomnographic finding in patients with MSA. RBD can frequently herald the appearance of other MSA symptoms by years. Extended polysomnographic montages are recommended in MSA sleep studies.  相似文献   

6.
Rats were tested in an instrumental lever pressing procedure, in which a computer program recorded detailed parameters of responding such as response initiation and duration. Initially, rats with ventrolateral striatal dopamine depletions and control rats were tested on days 3-5 after surgery. Dopamine depletions produced by local injections of 6-hydroxydopamine substantially reduced the number of lever presses emitted. Dopamine depleted animals showed significant increases in average response initiation times, average length of fast initiation times, average length of pauses and total pause time. The distribution of initiation times was altered so that DA depleted rats showed significant reductions in the relative number of very high rate responses and also showed increases in the relative number of pauses. On day 7 after surgery, dopamine-depleted rats received one of three drug treatments: injections of ascorbate vehicle, injections of 20.0 mg/kg L-DOPA, and injections of 40.0 mg/kg L-DOPA. Injections of 40.0 mg/kg L-DOPA led to some improvement in several parameters of instrumental responding. Compared to the previous baseline day, the group that received 40.0 mg/kg L-DOPA showed a significant increase in number of responses on the drug treatment day, and also showed significant decreases in average response initiation time and total pause time. The group that received 40.0 mg/kg L-DOPA also showed significant increases in number of responses (expressed as a percent of the previous day) when compared to the control group that received injections of ascorbate vehicle. These results indicate that L-DOPA can partially reverse the skilled motor deficits produced by ventrolateral striatal dopamine depletions, and suggest that this test may be useful for the assessment of antiparkinsonian drugs.  相似文献   

7.
Administration of L-DOPA to Parkinson patients has been suggested to exacerbate "functional denervation" of the nigrostriatal system. Therefore, experiments were conducted to determine if L-DOPA combined with the DOPA decarboxylase inhibitor, Ro4-4602 (benserazide hydrochloride) would potentiate amphetamine-induced neurotoxicity. Mice received two injections of saline or benserazide + L-DOPA (25.0 or 100.0 mg/kg) interspersed with four injections of amphetamine (15.0 mg/kg) at 2-h intervals. Significant depletion of striatal dopamine, DOPAC, and HVA was evident 1 wk following amphetamine administered with or without 25.0 mg/kg L-DOPA + benserazide, whereas 100.0 mg/kg L-DOPA + benserazide potentiated amphetamine-induced depletion of striatal dopamine (17 vs 28% of control values). This enhanced toxicity may be consequent to increased dopamine turnover following L-DOPA (360 vs 231%), a situation akin to that observed in compromised dopaminergic nigrostriatal systems of parkinsonian patients. Furthermore, striatal 5-HT was not altered by amphetamine alone, whereas concurrent administration of L-DOPA/ benserazide depleted 5-HT to 82% of control values. No changes were evident in the frontal cortex following amphetamine with or without concurrent L-DOPA/benserazide; however, L-DOPA/benserazide administered alone reduced 5-HT and 5-HT turnover to 58% of control values.  相似文献   

8.
OBJECTIVE: To evaluate the nonergot dopamine agonist ropinirole as an adjunct to L-dopa in a randomized, double-blind trial in PD patients with motor fluctuations. BACKGROUND: L-dopa in the treatment of PD is associated with motor fluctuations, dyskinesia, and other adverse effects. The use of dopamine agonists in the treatment of PD delays recourse to L-dopa and thus delays the possibility of adverse effect onset. METHODS: Ropinirole (n = 95) or placebo (n = 54) was added to L-dopa, and L-dopa was then reduced in a planned manner during the 6-month trial. RESULTS: A significantly greater number of ropinirole patients were able to achieve a 20% or greater reduction in both L-dopa dose and in percent time spent "off" compared with placebo (35.0% versus 13.0%; p = 0.003). The mean daily L-dopa dose was reduced significantly with ropinirole treatment (242 mg versus 51 mg; p < 0.001) as was the percent awake time spent "off" (11.7% versus 5.1%; p = 0.039). There was no difference in the percent of patients who withdrew because of adverse effects (15.8% on ropinirole versus 16.7% on placebo). CONCLUSIONS: Ropinirole permits a reduction in L-dopa dose with enhanced clinical benefit for PD patients with motor fluctuations.  相似文献   

9.
Oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) and dopamine (DA) to generate semiquinones/quinones, oxygen radicals, and other reactive oxygen species may play a role in neuronal cell death in Parkinson's disease (PD). In particular, semiquinones/quinones can form conjugates with thiol compounds such as GSH and cysteine. Exposure of L-DOPA, DA, and other catecholamines to a system generating O2.- radical led to O2(.-)-dependent depletion of added GSH (or cysteine), accompanied by the formation of thiol-DA or -DOPA adducts as detected by HPLC. Superoxide could additionally cause destruction of these adducts. Iron or copper ions could also promote conjugate formation between GSH or cysteine and DA and L-DOPA, especially if H2O2 was present. We applied HPLC to measure glutathionyl and cysteinyl conjugates of L-DOPA, DA, and 3,4-dihydroxyphenylacetic acid (DOPAC) in postmortem brain samples from PD patients and normal control subjects. Conjugates were detected in most brain areas examined, but levels were highest in the substantia nigra and putamen. In most regions, adduct levels were lower in PD, but there were significant increases in cysteinyl adducts of L-DOPA, DA, and DOPAC in PD substantia nigra, suggesting that acceleration of L-DOPA/DA oxidation occurs in PD, although we cannot say if this is a primary feature of the disease or if it is related to therapy with L-DOPA. In vitro, conjugate formation could be inhibited by the dithiol dihydrolipoate but not by its oxidised form, lipoic acid.  相似文献   

10.
High-performance liquid chromatography with electrochemical detection has been employed to analyze ultrafiltrates of cerebrospinal fluid of Parkinson's Disease (PD) patients and age-matched controls for the dopamine (DA) metabolites homovanillic acid (HVA) and 5-S-cysteinyldopamine (5-S-CyS-DA). The mean level of HVA in the CSF of PD patients, measured 5 days after withdrawal from L-DOPA therapy, was significantly lower than that measured in controls. By contrast, mean levels of 5-S-CyS-DA were not significantly different in the CSF of PD patients taking L-DOPA (PD-LT patients) the same patients 5 days after discontinuing this drug (PD-LW patients) or controls. However, the mean 5-S-CyS-DA/HVA concentration ratio was significantly (p < 0.05) higher in the CSF of PD-LW patients compared to controls. Although the PD patient population employed in this study had been diagnosed with the disease several years previously and had been treated with L-DOPA for prolonged periods of time the results of this study suggest that low CSF levels of HVA and a high 5-S-CyS-DA/HVA ratio together might represent useful markers for early diagnosis of PD. The high 5-S-CyS-DA/HVA ratio observed in the CSF of PD-LW patients also provides support for the hypothesis that the translocation of glutathione or L-cysteine into neuromelanin-pigmented dopaminergic cell bodies in the substantia nigra might represent an early event in the pathogenesis of PD.  相似文献   

11.
We assessed the effect of sleep benefit on motor performance in Parkinson's disease (PD) and analyzed its relation to pharmacologic and sleep measures. The sleep benefit phenomenon-motor improvement after sleep before drug intake-in patients with PD has been addressed by questionnaire studies, but objective data are scarce. Ten PD patients with sleep benefit were pairwisely matched to 10 PD patients without sleep benefit for gender, age, PD symptom duration, and medications. We examined motor performance at night before sleep, during morning baseline state immediately after spontaneous awakening, and continuously after intake of the usual levodopa dose. Plasma levodopa concentrations were measured serially and all-night polysomnography was performed. Between night and morning evaluations, motor state improved slightly in patients with sleep benefit and deteriorated slightly in patients without sleep benefit. The difference between both groups proved to be significant. After levodopa induced "on" state, patients with sleep benefit had more severe interdose "off" than those without. Levodopa concentrations and polysomnographic findings were similar in both conditions, although there was a trend toward more abnormal sleep measures in sleep benefit patients. Sleep benefit is a small but significant phenomenon. It does not clearly relate to a specific sleep variable; however, patients with sleep benefit showed a different response profile to levodopa. Subjective perception or possibly sensory mechanisms could play an additional role in sleep benefit in PD.  相似文献   

12.
A consistent neurochemical abnormality in Parkinson's disease (PD) is degeneration of dopaminergic neurons in substantia nigra, leading to a reduction of striatal dopamine (DA) levels. As tyrosine hydroxylase (TH) catalyses the formation of L-DOPA, the rate-limiting step in the biosynthesis of DA, the disease can be considered as a TH-deficiency syndrome of the striatum. Similarly, some patients with hereditary L-DOPA-responsive dystonia, a neurological disorder with clinical similarities to PD, have mutations in the TH gene and decreased TH activity and/or stability. Thus, a logical and efficient treatment strategy for PD is based on correcting or bypassing the enzyme deficiency by treatment with L-DOPA, DA agonists, inhibitors of DA metabolism, or brain grafts with cells expressing TH. A direct pathogenetic role of TH has also been suggested, as the enzyme is a source of reactive oxygen species (ROS) in vitro and a target for radical-mediated oxidative injury. Recently, it has been demonstrated that L-DOPA is effectively oxidized by mammalian TH in vitro, possibly contributing to the cytotoxic effects of DOPA. This enzyme may therefore be involved in the pathogenesis of PD at several different levels, in addition to being a promising candidate for developing new treatments of this disease.  相似文献   

13.
The consistent findings of decreased levels of the major antioxidant glutathione in substantia nigra of patients with idiopathic Parkinson's disease (PD) has provided most of the basis for the oxidative stress hypothesis of the etiology of PD. To establish whether a nigral glutathione deficiency is unique to PD, as is generally assumed, or is present in other Parkinsonian conditions associated with nigral damage, we compared levels of reduced glutathione (GSH) in postmortem brain of patients with PD to those with progressive supranuclear palsy (PSP) and multiple system atrophy (MSA). As compared with the controls, nigral GSH levels were decreased in the PD and PSP patient groups (P < 0.05 for PD [-30%], PSP [-21%]), whereas a similar decrease in the MSA patient group did not reach statistical significance (P = 0.078, MSA [-20%]). GSH levels were normal in all examined normal and degenerating extra-nigral brain areas in PSP and MSA. A trend for decreased levels of uric acid (antioxidant and product of purine catabolism) also was observed in nigra of all patient groups (-19 to -30%). These data suggest that glutathione depletion, possibly consequent to overutilisation in oxidative stress reactions, could play a causal role in nigral degeneration in all nigrostriatal dopamine deficiency disorders, and that antioxidant therapeutic approaches should not be restricted to PD.  相似文献   

14.
Oxidative stress may contribute to the neurodegenerative process in amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD). Motor cortex in PD is not affected and its inclusion in studies of free radical involvement in ALS pathogenesis could help elucidate whether oxidative stress is disease specific or a more widespread phenomenon present in the neurodegeneration. We have measured cytosolic and mitochondrial isoforms of superoxide dismutase (SOD), antioxidant enzymes involved in primary defence against free radical damage, in motor cortex of six patients with sporadic form of ALS (SALS), eight with PD and eight normal control subjects. We have found no difference in the activities of cytosolic and mitochondrial SOD between SALS and control motor cortex. Mitochondrial SOD activity in PD motor cortex was, however, significantly higher than in SALS and control motor cortex whereas activity of cytosolic SOD was lower than in two other groups although the differences were not statistically significant. Our findings indicate the presence of an altered antioxidant defence system in PD but not ALS upper motor neurons, suggesting that oxidative stress may be a widespread phenomenon in PD.  相似文献   

15.
We investigated the number of tyrosine hydroxylase (TH)-immunoreactive neurons in the C1 and A2 regions of the medulla, the sites of the baroreflex arc, in 7 patients with multiple system atrophy (MSA), 8 with Parkinson's disease (PD), 9 with amyotrophic lateral sclerosis (ALS), and 12 age-matched normal subjects to analyze the relationship between cardiovascular dysfunction and medullary catecholaminergic neurons. Orthostatic hypotension (OH) was marked in all the MSA patients and moderate in three PD patients. Three of the five ALS patients who had been on respirators showed lability of blood pressure; paroxysmal hypertension and nocturnal hypotension without compensatory tachycardia. All the MSA patients showed extremely marked decrease of TH-immunoreactive neurons in both the C1 and A2 regions. In the patients with Parkinson's disease, numerous TH-immunoreactive neurons contained Lewy bodies that were immunostained by antibody to TH. TH-immunoreactive neurons were decreased very markedly in the A2 regions of two patients with OH, and three patients without OH showed fairly marked decreases in the C1 or A2 region. In contrast, the number of TH-immunoreactive neurons in ALS was the same as in normal subjects. In MSA and some PD patients, orthostatic hypotension may partly be due to the involvement of the medullary catecholaminergic neurons. The lability of blood pressure in ALS probably is not related to the medullary catecholaminergic neurons.  相似文献   

16.
BACKGROUND: The functional assessment of the startle circuit is usually done by analyzing the acoustic startle response (ASR). However, a startling acoustic stimulus (SAS) also induces changes in the excitability of neural structures that can be demonstrated by studying the SAS-induced change in the behavior of certain neurophysiologic responses. OBJECTIVE: To examine the effects induced by an SAS on voluntary reaction time in patients with parkinsonian syndromes (StartReact effect) and to compare the results with those obtained in a group of age-matched healthy volunteers. METHODS: Twelve patients with idiopathic PD (IPD), seven patients with progressive supranuclear palsy (PSP), seven patients with multisystem atrophy (MSA), and seven healthy age-matched control volunteers performed a simple visual reaction time task and received SAS together with the "go" signal in random trials. RESULTS: Baseline reaction time was significantly slower in PSP patients than in control subjects and MSA patients. The SAS induced a significant shortening of the reaction time in control subjects and in patients with IPD and MSA, but not in patients with PSP. The percentage of reaction time shortening with regard to the baseline values also differed significantly between PSP patients and the other groups of subjects. The StartReact effect was consistent throughout the experiment and showed reduced habituation with repeated testing. CONCLUSIONS: The results are consistent with an abnormal function of the startle circuit in patients with PSP and agree with previous studies using the ASR. The reduced habituation of the StartReact effect favors its clinical applicability in the assessment of differences between patients with parkinsonian syndromes.  相似文献   

17.
Although clinical rating scales and simple timed tests of motor function are widely used to assess motor response to therapy, gait analysis may provide an alternative measure of this response. We studied 15 patients with PD complicated by motor fluctuations, first to determine changes in temporal and spatial gait parameters following levodopa, secondly to assess the stability of repeated gait measures and timed tests in "off" and "on" states, and thirdly to determine the use of gait analysis in the assessment of the dopaminergic response. Gait analysis (velocity, stride length, cadence, and double limb support), clinical rating scales (modified Webster scale and Hoehn and Yahr stage), and timed tests of motor function (hand tapping and stand-walk-sit time) were performed before ("off") and after ("on") a levodopa challenge. Stride length and gait velocity increased following medication whereas cadence and double limb support did not. Most gait measures and the stand-walk-sit time were stable over three consecutive trials in both "off" and "on" states. Of the gait measures, only cadence in the "off" state changed significantly whereas the tapping count improved with repeated trials in both "off" and "on" states. Changes in stride length, gait velocity, and tapping count following levodopa correlated with changes in clinical rating scales following treatment. Measurement of gait parameters provides a reliable, objective alternative to rating scales and timed tests in assessing the dopaminergic response in patients with PD and motor fluctuations.  相似文献   

18.
Lewy bodies in Parkinson' s disease (PD) are strongly immunoreactive with antibodies against alpha-synuclein, which is mutated in some familial cases of the disease. We carried out immunohistochemical examinations of the brains of multiple system atrophy (MSA) patients using anti-alpha-synuclein antibodies. Strong alpha-synuclein immunoreactivity was found in glial cytoplasmic inclusions (GCIs), which are of oligodendroglial origin and occur exclusively in MSA. Alpha-synuclein-immunoreactive neuronal cytoplasmic inclusions (NCIs) were also found occasionally in the substantia nigra, pontine and inferior olivary nuclei, and dentate fascia. These findings indicate that alpha-synuclein is also a major component of GCIs and NCIs in MSA and strongly suggest that alpha-synuclein aggregation is a common process in certain neurodegenerative diseases, including PD and MSA.  相似文献   

19.
Electroconvulsive therapy (ECT) was given to 16 non-depressed, non-demented patients with advanced Parkinson's disease (PD). In all the patients an antiparkinsonian effect was seen, lasting for 18 months in one patient, 3-5 months in seven patients, and a few days to four weeks in eight patients. After ECT the levels of homovanillic acid and neuropeptide Y in cerebrospinal fluid (CSF) were significantly increased. The eight patients with long lasting motor improvement after ECT had significantly lower CSF-3-methoxy-4-hydroxyphenylglycol compared to the group with short lasting improvement. Five patients developed transitory mental confusion after ECT. In these patients, and in no others, a high albumin-ratio was found already before ECT was given - an indication of blood CSF barrier damage. Our results suggest that ECT is valuable in patients with drug refractory PD or PD with intolerance to antiparkinsonian drugs.  相似文献   

20.
Sensory and motor symptoms of the limbs, motor restlessness and an urge to move only at rest are the characteristics of the restless legs syndrome (RLS), which often leads to severe sleep disturbances. The clinical diagnosis can be made on the basis of the typical history, normal neurological findings and, in some cases, a positive family history, and can be confirmed by polysomnography. The indication for treatment depends on the patient's discomfort and the severity of the sleep disturbances. L-DOPA is the treatment of first choice both in idiopathic and uremic RLS. A bedtime dose of 100-200 mg L-DOPA standard plus decarboxylase inhibitor is effective against mild and moderate sleep disturbances in RLS. Titration of the dosage and additional treatment with sustained-release preparations of L-DOPA should be applied individually. Opioids and dopamine agonists are effective alternative treatments in idiopathic RLS. Benzodiazepines are indicated only in individual cases. Besides L-DOPA, uremic RLS patients can be treated with opioids and benzodiazepines. Various approaches in the treatment of idiopathic and uremic RLS are reviewed and the practical management of therapy is outlined.  相似文献   

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