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)

Spasticity in man is presented as a disinhibition of spinal cord mechanisms, the responses to stretch depending on the interaction of the reflex effects of group Ia with those of group II afferent fibres. The reflex responses to muscle stretch and shortening in Parkinson's disease do not depend on an abnormality of spinal reflex mechanisms. The superimposition of physiological tremor or alternating tremor in rigidity produces the classical cog-wheel sensation. The phase lead of the action tonic stretch reflex was found to be reduced in patients with athetosis and cerebellar disease, thus diminishing damping of unwanted movements. The more complex transmission characteristics of the action tonic stretch reflex of normal man are absent in patients with spasticity and cerebellar lesions, presumably due to interference with long-loop pathways. In normal subjects gain of the reflex loop increases with voluntary contraction but in spasticity gain remains high irrespective of contraction level.
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PMID:A physiological approach to motor disorders. 15 18

The antiparkinsonian activity of lergotrile mesylate, a presumed dopaminergic receptor stimulating agent, was investigating in monkeys with surgically induced tremor and in parkinsonian patients. The administration of lergotrile resulted in a dose-dependent reduction in the intensity of tremor in the monkeys. In 13 patients with Parkinson's disease treated with lergotrile (up to 12 mg a day), overall improvement was observed in five. Tremor was the main clinical feature to benefit, and the improvement reached statistical significance. In a subgroup of four patients treated with a higher dose of lergotrile (up to 20 mg a day), further improvement in rigidity and bradykinesia was noted, but again, only improvement in tremor was statistically significant. Adverse effects included orthostatic hypotension, behavioral alterations, and nausea and vomiting. These were severe enough to result in drug withdrawal in three patients.
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PMID:Studies on the antiparkinsonism efficacy of lergotrile. 16 32

The effect of a new dopamine receptor stimulating agent, piribedil (ET 495), was studied in 10 patients with Parkinson's syndrome, who had had no or a poor response to previous L-DOPA treatment, or had displayed marked side effects during L-DOPA administration. Piribedil produced significant improvement of the functions of activity of daily living (ADL), and appeared to have a preferential effect on parkinsonian tremor. However, treatment was difficult to control primarily because of severe psychiatric side effects.
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PMID:Piribedil in Parkinson's syndrome: a clinical study. 18 60

Paralysis agitans may be mimicked by other disease processes and drugs which disturb the structural or functional integrity of the dopaminergic nigrostriatal system. In another group of patients, isolated symptoms or signs such as tremor or increased muscle tone are considered out of the context of the total clinical picture and may suggest parkinsonism.
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PMID:Differential diagnosis of paralysis agitans. 26 20

In principle tremors can be produced by (1) mechanical oscillators (combination of masses and springs), (2) reflex oscillators arising from sensory feedback pathways, or (3) central oscillators generated by single "pacemaker" neurones or interconnected networks. Recent studies supporting each of these mechanisms under certain conditions are discussed. Differences between these mechanisms are clarified by recent studies in Edmonton on the premammillary cat. This preparation shows a prominent reflexly-induced tremor which can be modified by mechanical loading and electrical stimulation. It also shows spontaneous stepping on a treadmill which is known to be produced by a spinal "stepping generator", but can be modified in interesting ways by sensory perturbations. The applicability of these animal studies to human tremors is considered in relation to preliminary studies in Calgary on patients with Parkinson's disease or essential tremor. We have attempted to modify these tremors by application of torque pulses applied to the wrist. The results are described in terms of a normalized "resetting" index which has a high value (greater than 0.6) for all essential tremor patients studied, and a wide range of values for different parkinsonian patients. The resetting index may be useful in determining the relative importance of peripheral and central factors in producing tremor in a variety of patients.
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PMID:Modifications of ongoing tremors and locomotion by sensory feedback. 28 51

Nine patients suffering from Parkinson's disease and 2 cases of Parkinsonian syndrome were treated with bromocriptine, for 41 to 117 days, with a daily dose of 20 to 40 mg. The results were very good in 4 cases, satisfactory in 6 and nil in one case. Improvement concerned akinesias, rigidity and tremor, and was more marked in patients with more advanced signs. In 2 patients, amantadine was stopped. The dose of L-dopa was decreased by 2/3 without any change in clinical condition and L-dopa could be withdrawn in 5 cases out of 8. Bromocriptine appears to be an interesting development in the treatment of Parkinson's disease.
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PMID:[Treatment of parkinsonian syndromes by bromocriptin]. 31 21

After a preliminary study in 6 parkinsonian patients concerning the effectiveness and tolerance of 1,3-dimethyl-5-aminoadamantane hydrochloride (memantine) an investigation to assess its short-term effects was performed. In an unselected group of 12 parkinsonian patients 40 mg of memantine diluted in 500 ml of laevulose were applied i.v. within 2 h. The patients were examined under standardized conditions before, immediately after and 2, 4 and 24 h, respectively, using a program of physchological tests. The results give evidence for a favourable influence on rigor and tremor in Parkinson's syndrome as well as on motor drive. In comparative studies memantine showed a better tolerance than adamantylaminosulfate. The short-time effects of the drug could be differentiated from placebo and learning effects.
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PMID:[Effects of intravenous administration of memantine in parkinsonian patients (author's transl)]. 33 93

Lergotrile mesylate, an ergot alkaloid derivative and putative dopamine agonist, was effective in the majority of patients with Parkinson's disease who were showing signs of disease progression despite treatment with levodopa combined with a peripheral decarboxylase inhibitor (carbidopa). Among 20 patients completing a six-month trial, there was a significant (P less than .01) reduction in rigidity, tremor, bradykinesia, gait disturbance, and total score when lergotrile was added to levodopa plus carbidopa. Mean daily dose of lergotrile mesylate was 52 mg, and the mean daily dose of levodopa was reduced by 15%. Abnormal involuntary movements were decreased on addition of lergotrile and reduction in levodopa while mental changes and orthostatic hypotension were increased. Elevations in serum transaminase levels were noted in three patients. The ergot alkaloids promise to be an important new class of antiparkinsonian drugs.
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PMID:Treatment of Parkinson's disease with lergotrile mesylate. 33 94

The comparison of the blood pressures of 273 patients with Parkinson's disease and of controls matched in sex and age revealed that Parkinsonian patients had a lower systolic blood pressure and more rarely suffered from clinical hypertension than did the control subjects. Among the Parkinsonian patients both the systolic and diastolic blood pressures decreased with advancing stages of the disease. The severity of tremor did not correlate significantly with the level of the blood pressure, but with increasing severity of rigidity and hypokinesia the blood pressure lowered significantly.
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PMID:Level of blood pressure in patients with Parkinson's disease. A case-control study. 35 39

In a study of 16 psychotic patients with neuroleptic-induced tardive dyskinesia and 16 patients with Parkinson's disease and L-Dopa-induced hyperkinesia it was found that (1) tardive dyskinesia, compared to L-Dopa hyperkinesia, was localized almost exclusively to the oral region (P mean value of 0.01), whereas theL-Dopa hyperkinesia was more pronounced in the neck (P mean value of 0.05) and the extremities (P mean value of 0.05); (2) L-Dopa hyperkinesia showed an increasing tendency to oral preponderance with age, irrespective of the severity ofParkinsonism and extra-oral hyperkinesia, while tardive dyskinesia only itensified with age, without any change in distribution; and (3) extra-oral L-Dopa hyperkinesia was related to the localization and severity of pretreatment Parkinsonism, and more to bradykinesia than to rigidity and tremor. It is concluded that the irreversible neurotoxic effect of neuroleptic drugs may be associated with age-related changes in the oral somatotopic region of the basal ganglia (to be given consideration in any future search for the pathogenetic process underlying irreversible tardive dyskinesia), and that the pathophysiology of involuntary hyperkinesia in neuroleptic-treated psychiatric patients and in L-Dopatreated parkinson patients may consist of a primary dopamine deficiency (pharmacological or structural), and a secondary relative hyperactivity in the dopaminergic system ("dopaminergic hypersensitivity") possibly corresponding to hypoactivity in the cholinergic system.
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PMID:Relationship between tardive dyskinesia, L-Dopa-induced hyperkinesia and parkinsonism. 40 41


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