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)

Budipine is a novel antiparkinsonian drug which is particularly beneficial in the treatment of parkinsonian tremor. The mechanism of action of budipine is not fully understood. To study whether budipine has dopaminergic activity in vivo, we used the 6-hydroxydopamine rotational model of Parkinson's disease. Budipine (0.78-12.5 mg/kg i.p.) did not induce ipsilateral or contralateral rotations, suggesting that it does not possess direct or indirect dopaminergic activity. This conclusion is further supported by the observation that budipine (10 mg/kg) i.v. did not facilitate striatal dopamine release measured in vivo by brain microdialysis. To investigatate possible antimuscarinic and N-methyl-D-aspartic acid (NMDA) antagonistic properties of budipine, we compared budipine with the antimuscarinic antiparkinsonian drug biperiden and the NMDA receptor antagonist 3-[(+/-)-2-carboxypiperazine-4-yl]-propyl-1-phosphonic acid (CPP). In receptor-binding assays, budipine inhibited thienylcyclohexylpiperidyl-3,4-[3H](n) ([I3H]TCP) (2.5 nM)-binding with an IC50 of 36 microM and [3H]3-quinuclidinol benzilate-binding with an IC50 of 1.1 microM. The respective values for biperiden were 170 and 0.053 microM. In line with these findings, budipine and CPP increased the threshold for NMDA-induced seizures in mice with an ED50 of 10.2 and 4.4 mg/kg, respectively, whereas biperiden was not effective. In 6-hydroxydopamine-lesioned rats, budipine (3.13-12.5 mg/kg) and CPP (0.1-0.39 mg/kg) increased the number of contralateral rotations induced by apomorphine, whereas biperiden was not effective. The present data suggest that budipine acts by blocking muscarinic and NMDA transmission while facilitation of dopaminergic transmission does not appear to contribute to its in vivo action. In comparison to biperiden, which has also antimuscarinic and NMDA receptor antagonistic properties, the anti-NMDA action of budipine is more prominent.
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PMID:Effects of the antiparkinsonian drug budipine on central neurotransmitter systems. 877 48

The present behavioral study was undertaken to investigate whether neuronal nitric oxide (NO) synthase mediates the abnormal consequences of increased NMDA receptor-mediated synaptic transmission in models of postural tremor, Parkinson's disease and epilepsy. We used 7-nitroindazole, a selective inhibitor of neuronal NO synthase, and NG-nitro-L-arginine (L-NAME), an unspecific NO synthase inhibitor, and compared their action with that of the competitive NMDA receptor antagonist 3-[(R)-2-carboxypiperazin-4-yl]-prop-2-enyl-1-phosphonic acid (D-CPPene). In both mice and rats, 7-nitroindazole, L-NAME and D-CPPene dose dependently reversed the harmaline-induced increase of cerebellar cyclic guanosine-5'-monophosphate (cGMP) levels. For subsequent behavioral experiments we used doses of 7-nitroindazole, L-NAME and D-CPPene which were equipotent in preventing harmaline-induced cGMP increase. Harmaline-induced tremor in mice and rats was suppressed by D-CPPene, but not by 7-nitroindazole or by L-NAME. This effect of D-CPPene was not due to unspecific suppression of motor activity, since D-CPPene did not affect locomotor activity at doses which reduced tremor. D-CPPene, but not 7-nitroindazole and L-NAME potentiated the antiparkinsonian action of the dopamine agonist lisuride in rats with unilateral 6-hydroxydopamine lesions of the substantia nigra. D-CPPene antagonized seizures induced by intracerebroventricular injection of NMDA in mice. In contrast, 7-nitroindazole and L-NAME had only a tendency to prevent seizures and to delay the latency to onset of seizures. We conclude from these results that neuronal NO synthase does not serve as a major mediator of increased NMDA receptor-mediated synaptic transmission in animal models of Parkinson's disease, postural tremor and epilepsy. The novel observation that D-CPPene suppresses harmaline-induced tremor leads us to suggest that NMDA receptor antagonists should be considered as novel therapeutics for postural tremor.
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PMID:Effects of 7-nitroindazole, NG-nitro-L-arginine, and D-CPPene on harmaline-induced postural tremor, N-methyl-D-aspartate-induced seizures, and lisuride-induced rotations in rats with nigral 6-hydroxydopamine lesions. 890 Oct 1

The autopsy findings of a 14-year-old Japanese girl with Ewing's sarcoma, who had multiple neurofibrillary tangles and Lewy bodies and hemiatrophy of the central nervous system (CNS), are reported. She had retinoblastoma of her right eye 8 months after birth, which was treated with chemotherapy and irradiation (40 Gy), twice, seizures 1 year and 2 months after birth, and thereafter severe mental retardation. She showed left hemiparesis after a febrile seizure at the age of 7 years and CT disclosed the right cerebral hemiatrophy. For the last 2 years of life she suffered from Ewing's sarcoma. Extrapyramidal signs were absent. Neuropathologically, tangles consisting of paired helical filaments were distributed symmetrically in virtually all the grey matter. They were particularly numerous in the frontal cortex and substantia nigra, but sparse in the nucleus of Meynert, hippocampus, and brainstem. Several Lewy bodies, which were ultrastructurally identical to those seen in Parkinson's disease, were present in the substantia nigra (more on the left than right) and locus coeruleus. Morphometrically, the number and size of substantia nigral neurons were reduced, the reduction in the latter being more marked than the former, but the melanin pigment contents and shapes of the remaining neurons appeared normal. The right cerebral hemiatrophy with contralateral cerebellar hemiatrophy may have been attributable to irradiation. Although our patient did not have parkinsonism, her features resembled those of a 28-year-old autopsy case reported by Popovich et al. [1987].
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PMID:A 14-year-old patient with Ewing's sarcoma presenting at autopsy with multiple neurofibrillary tangles and Lewy bodies in addition to hemiatrophy of the central nervous system. 910 Nov 9

RECENT DESCRIPTION: Recent report have described "atypical" familial extrapyramidal syndromes similar to authentic Parkinson's disease and well-defined genetic diseases. PERRY SYNDROME: Onset occurs between 35 and 57 years, leading to death within 3 to 7 years. The syndrome associates a Parkinson's syndrome, athymormia and hypoventilation. Massive neuronal depopulation in the locus niger and rare Lewy bodies are seen. PARKINSON'S SYNDROME WITH PERIPHERAL NEUROPATHY: In addition to the extrapyramidal signs, there is ptosis, neuropathy and sometimes dementia and major neurone loss in the locus niger. No Lewy bodies have been identified. PARKINSON'S SYNDROME WITH PALLIDOPONTONIGRAL DEGENERATION: Onset occurs between 32 and 58 years, leading to death within 8 years. Extrapyramidal signs, falls, supranuclear palsy and dementia are observed. Neurone loss is severe in the pars compacta, locu sniger, palladium, pons, and mesencephalic tegmentum. There are no Lewy bodies. EARLY-ONSET PARKINSON'S SYNDROME: Beginning between 2 and 39 years, there are no associated neurological signs. Severe neurone loss in the pars compacta and the pars reticulata of the niger locus without Lewy bodies. PARKINSON'S SYNDROME-DEMENTIA WITH "BALLOON NEURONES": This syndrome begins at 24-59 years and leads to death in 8 to 11 years. There are extrapyramidal signs, a pyramidal syndrome, dementia, generalized seizures and dysautonomia. Major neurone loss occurs with balloon neurones in the anterior temporal cortex, the amygdala, the parahippocampal gyrus, the hypothalamus, the dorsal nucleus of the X and rare Lewy bodies. PARKINSON'S SYNDROME FRONTAL DEMENTIA AND AMYOTROPHY: Beginning between 27 and 56 years, the syndrome leads to death in 13 years and associates frontal dementia with motor neurone defects with the extrapyramidal signs. There is neurone loss in the locus niger and amygdala as well as in the anterior horn of the cord. There are no Lewy bodies. SPECIFIC CLINICOPATHOLOGICAL ENTITIES: is the most likely hypothesis. There is no anatomoclinical evidence suggesting these syndromes should be considered to be Parkinson's disease.
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PMID:[Atypical familial parkinsonian syndromes. Parkinson diseases or specific entities?]. 912 34

A series of substituted 9,10-dihydroxyhexahydrobenzo[f]thieno[c]quinolines (TB[f]Q), varying with respect to the position of the thiophene relative to the benzo[f]quinoline core and the nature and position of the substituent on the thiophene, were prepared and evaluated for their affinity and selectivity for the dopamine D1-like receptor. The thieno[3,2-c]B[f]Q regioisomers bearing a small alky1 (C1-C3) substituent at the 2 position were potent (Ki < 20 nM) and selective (D2/D1 > 50) D1 agonists with close to full agonist activity (IA > 85%). The compounds were resolved and found to exhibit a high level of enantiospecificity in their interaction with the D1 receptor. Selected compounds were tested in vivo in the 6-OHDA rodent model of Parkinson's disease and for their liability to produce seizure-like activities in mice. (5aR)-trans-2-Propyl-4,5,5a,6,7, 11b-hexahydro-3-thia-5-azacyclopent-1-ena[c]phenanthrene-9,10-diol (5) emerged as the compound with the best overall in vivo profile in terms of potency (ED50 = 0.04 mumol/kg) and safety.
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PMID:Substituted hexahydrobenzo[f]thieno[c]quinolines as dopamine D1-selective agonists: synthesis and biological evaluation in vitro and in vivo. 917 69

Zinc is an important trace element in biology. An important pool of zinc in the brain is the one present in synaptic vesicles in a subgroup of glutamatergic neurons. In this form it can be released by electrical stimulation and may serve to modulate responses at receptors for a number of different neurotransmitters. These include both excitatory and inhibitory receptors, particularly the NMDA and GABA(A) receptors. This pool of zinc is the only form of zinc readily stained histochemically (the chelatable zinc pool), but constitutes only about 8% of the total zinc content in the brain. The remainder of the zinc is more or less tightly bound to proteins where it acts either as a component of the catalytic site of enzymes or in a structural capacity. The metabolism of zinc in the brain is regulated by a number of transport proteins, some of which have been recently characterized by gene cloning techniques. The intracellular concentration may be mediated both by efflux from the cell by the zinc transporter ZrT1 and by complexing with apothionein to form metallothlonein. Metallothionein may serve as the source of zinc for incorporation into proteins, including a number of DNA transcription factors. However, zinc is readily released from metallothionein by disulfides, increasing concentrations of which are formed under oxidative stress. Metallothionein is a very good scavenger of free radicals, and zinc itself can also reduce oxidative stress by binding to thiol groups, decreasing their oxidation. Zinc is also a very potent inhibitor of nitric oxide synthase. Increased levels of chelatable zinc have been shown to be present in cell cultures of immune cells undergoing apoptosis. This is very reminiscent of the zinc staining of neuronal perikarya dying after an episode of ischemia or seizure activity. Thus a possible role of zinc in causing neuronal death in the brain needs to be fully investigated. intraventricular injections of calcium EDTA have already been shown to reduce neuronal death after a period of ischemia. Pharmacological doses of zinc cause neuronal death, and some estimates indicate that extracellular concentrations of zinc could reach neurotoxic levels under pathological conditions. Zinc is released in high concentrations from the hippocampus during seizures. Unfortunately, there are contrasting observations as to whether this zinc serves to potentiate or decrease seizure activity. Zinc may have an additional role in causing death in at least some neurons damaged by seizure activity and be involved in the sprouting phenomenon which may give rise to recurrent seizure propagation in the hippocampus. In Alzheimer's disease, zinc has been shown to aggregate beta-amyloid, a form which is potentially neurotoxic. The zinc-dependent transcription factors NF-kappa B and Sp1 bind to the promoter region of the amyloid precursor protein (APP) gene. Zinc also inhibits enzymes which degrade APP to nonamyloidogenic peptides and which degrade the soluble form of beta-amyloid. The changes in zinc metabolism which occur during oxidative stress may be important in neurological diseases where oxidative stress is implicated, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS). Zinc is a structural component of superoxide dismutase 1, mutations in which give rise to one form of familiar ALS. After HIV infection, zinc deficiency is found which may be secondary to immune-induced cytokine synthesis. Zinc is involved in the replication of the HIV virus at a number of sites. These observations should stimulate further research into the role of zinc in neuropathology.
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PMID:Zinc metabolism in the brain: relevance to human neurodegenerative disorders. 936 Dec 93

The adenosine A2A receptor subtype is one of the four adenosine receptors that have been identified in the mammalian organism. In addition to being found in blood vessels, platelets and polymorphonuclear leukocytes, the A2A receptors are abundant in the central nervous system, especially in the striatum. The recent development of selective A2A receptor ligands, in particular of receptor antagonists, makes it possible to elucidate the function of A2A receptors in normal and altered conditions. Pharmacological studies have shown that A2A receptor antagonists are potentially effective for treatment of neurodegenerative processes such as Parkinson's disease. Their activity is attributed to the close anatomical and functional links between A2A receptors and dopaminergic pathways in the basal ganglia. More recently, A2A receptor antagonists have proved to be active in models of cerebral ischemia. While the mechanisms underlying the role of A2A receptors in the hypoxia/ ischemia processes remains to be clarified, it is recognized that A2A receptor antagonists counteract the effects of excitatory aminoacids, which are massively released after cerebral ischemia. Another function of A2A receptors is related to protection from seizures, but further studies are needed to elucidate their specific interaction, if any, with neuronal excitability. Altogether, the great advance recently made with the discovery of selective A2A receptor ligands provides increasing information on the function of A2A receptors and opens new perspectives for treatment of neurological disorders.
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PMID:Adenosine A2A receptors and neuroprotection. 936 73

The authors examined the British medical literature published in the 45-year-period following Parkinson's treatise on the shaking palsy to determine the number and type of references to the shaking palsy or paralysis agitans during this particular period. Several sources suggest that Parkinson's 1817 treatise on the shaking palsy received little immediate attention in his native country, England, and that not until 1861, in France, did Charcot began to elucidate the clinical features of this entity, separating it from other neurologic disorders (for example, multiple sclerosis). A review of the British medical literature from the 45-year-period 1817-1861 revealed a number of references to paralysis agitans, including those by Cooke (1820), Good (1824 and 1829), Elliotson (1827, 1829, 1830, 1831, and 1833), Gowry (1831), anonymous (1832), Todd (1833), Watson (1836), Gibson (1839), Hall (1838 and 1841), Thompson (1842), Graves (1843), Birkett (1853), Paget (1855), and Reynolds (1855). Many of these did not report new or personally observed cases, did not separate Parkinson's disease from other disease entities characterized by both "shaking" and "palsy" (for example, tonic-clonic seizures), or misattributed motor signs to dysfunction of the pyramidal system rather than an extrapyramidal system (that is, attributing bradykinesia or rigidity to weakness). Although there were several references to "shaking palsy" in the early- to mid-19th-century British medical literature, there were few original case reports of Parkinson's disease. This may have contributed to the fact that during this period little was added to the original observations made by Parkinson in 1817. In particular, the separation of bradykinesia and weakness did not become apparent until later work by the French.
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PMID:The shaking palsy, the first forty-five years: a journey through the British literature. 939 40

In the last decade, a new electrophysiological tool has become available since the development of painless magnetic stimulators able to activate the primary motor cortex and the motor roots in conscious man. Therefore, it became possible to measure the conduction time within fast-conducting central motor pathways by substracting from the total latency of muscle responses elicited by cortical stimuli the conduction time in peripheral nerves. This technique proved sensitive enough to illustrate early abnormalities of central motor conduction in various neurological diseases such as multiple sclerosis, amyotrophic lateral sclerosis, cervical spondylotic myelopathy, degenerative ataxias or hereditary spastic paraplegias. When recorded early after stroke, motor evoked potentials are also a valuable tool to predict functional outcome. They can also illustrate subtle pathophysiological disturbances in diseases where there is no direct involvement of central motor pathways such as Parkinson's disease, dystonia or epilepsy. Magnetic cortical stimulation also offers unique opportunities to explore intracerebral inhibitory and excitatory circuits and mechanisms of brain plasticity. The recent development of rapid rate stimulators also enables functional studies of non-motor cerebral regions such as visual or frontal cortices. Moreover, rapid rate stimulation seems useful in the treatment of drug-resistant depression but the safety of this procedure, particularly with regard to the production of seizures or kindling, remains to be fully documented.
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PMID:[Applications of cortical magnetic stimulation]. 956 96

Hallucinations, sensory perceptions without environmental stimuli, occur as simple experiences of auditory, gustatory, olfactory, tactile, or visual phenomena as well as mixed- or complex experiences of more than one simple phenomenon. The nature of the hallucination assists localization, differential diagnosis, and treatment planning. In particular, the presence of persistent visual hallucinations of persons with Parkinson's disease predicts dementia, rapid deterioration, permanent nursing home placement, and death. Hallucinations in persons with Alzheimer's disease are often associated with serious behavioral problems and predict a rapid cognitive decline. Theories of the etiology of hallucinations include (1) stimulation, e.g., neurochemical, electrical, seizure, and ephaptic, and (2) inhibition, e.g., destruction of normally inhibitory functions, resulting in disinhibition as in the Charles Bonnet and phantom limb syndromes. Functional neuroimaging procedures suggest anatomical associations for hallucinations. While hallucinations may be a symptom of medical, neurologic, and psychiatric disorders, they may also occur in a wide range of human experiences.
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PMID:Hallucinations. 965 80


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