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 motor effects of selective D-1 dopamine receptor stimulation in Parkinson's disease have been explored in a limited number of studies with partial D-1 agonists only and the results were unsatisfactory. Four 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-exposed parkinsonian monkeys already exhibiting levodopa- and dopamine agonist-induced dyskinesia received selective D-1 agonists ([2,3,4,5-tetrahydro-7-8-dihydroxy-1-phenyl-1-H-3-benzazepine- HCI] (SKF 38393), [(+-)6-chloro-7,8-dihydroxy-3-allyl-1-phenyl-2,3,4,5-tetrahydro- 1H-3-benzazepine hydrobromide] (SKF 82958), [(1R, 3S)3-(1'-adamantyl)-1-aminomethyl-3,4-dihydro-5,6- dihydroxy-1H-2-benzopyran hydrochloride] (A-77636) and [(-)-(6aR)(12bR)-4,6,6a,7,8,12b-hexahydro-7-methyli ndolo (4,3-ab)-phenanthridine] (CY 208-243)) to compare these drugs with selective D-2 agonists (LY 171555, (+)-4-propyl-9- hydroxynaphthoxazine and bromocriptine) and levodopa in terms of antiparkinsonian efficacy and side effects. The D-1 class of compounds was as efficacious as the D-2 agents in alleviating parkinsonism in these animals. However, D-1 agonists were, in general, less likely to reproduce dyskinesia. In addition, D-1 agonists occasionally improved motor symptoms without concomitant dyskinesia, unlike D-2 agonists or levodopa (which always produced some dyskinesia with improvement in motor function). These preliminary results do not support the hypothesis that preferential D-1 receptor stimulation facilitates dyskinesia in primates.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Differential effect of selective D-1 and D-2 dopamine receptor agonists on levodopa-induced dyskinesia in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine- exposed monkeys. 790 95

We report a 85-year-old woman who had an onset of gait disturbance at 80 years of the age. She had a dizzy spell when she was 80-year-old. She was evaluated at another hospital where paroxysmal tachycardia and sinus arrest lasting as long as 5.8 seconds were found. She was diagnosed as having sick sinus syndrome and a pace maker was inserted. She had a gradual onset of disturbance of gait shortly after the above dizzy spell. She became unable to walk fast and her steps became small. Neurologic examination at age 83 revealed small step gait with freezing episodes. Retropulsion was present. No motor weakness or origidity was noted. She had no tremor. Mentally she was alert and sound. Cranial nerves were essentially normal. Cranial CT scan revealed slight diffuse low density change in the bilateral cerebral white matter. She was treated with amantadine HCI and levodopa with carbidopa. Her gait and balance showed some improvement. She developed pneumonia and worsening of her gait when she was 85 years of the age, and she was admitted again to our hospital. She was mentally alert and sound but she showed marked freezing of gait with loss of postural reflex; she would have fallen down unless supported upon standing. Cranial nerves were again essentially normal. Her hospital course was complicated by pneumonia, DIC, and renal failure. She expired suddenly on the 10th day of her last admission. She was discussed in a neurological CPC and the chief discussant arrived at the conclusion that the patient had vascular parkinsonism due to lacunar state. However, paucity of vascular changes in her CT scan remained as a question. Other participants thought that she had nigral cell loss secondary to her aging and circulatory disturbance which would have been caused by her sick sinus syndrome. Post-mortem examination revealed marked loss of nigral pigmented cells; the cell loss was diffusely seen in the substantia nigra. Neurofibrillary tangles were seen in the remaining neurons. In addition, gliosis was noted in the globus pallidus and the subthalamic nucleus, however, neuronal loss was very mild in those nuclei. In the superior colliculus, neuronal loss was mild, however, gliosis was seen. No clear neuronal loss was observed in the locus coeruleus, however, Lewy bodies were seen in the remaining neurons. Furthermore, Lewy bodies were also found in the substantia sigra. It was thought that she had progressive supranuclear play (PSP). Question was whether or not she was complicated by Parkinson's disease. Clinically, she had no rigidity or tremor. Pathologically, locus coeruleus did not show neuronal loss. Therefore, incidental Lewy body disease was raised as a possibility. Finally, it should be pointed out that she had no oculomotor disturbance or dementia, yet she had PSP. Her clinical features were those of pure akinesia. Pathologic changes were also relatively mild except for those in the substantia nigra. Possibility of post-encephalitic parkinsonism without encephalitis was also discussed, however, over all distribution of her pathologic changes was more consistent with PSP.
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PMID:[A 85-year-old woman with the onset of progressive gait disturbance at 80 years of the age]. 912 48

Methamphetamine (METH)-induced neurotoxicity within the striatum and substantia nigra of the vervet monkey was characterized by heterogeneous decreases in immunoreactivity (IR) for dopamine system phenotypic markers. Decreases in IR for tyrosine hydroxylase (TH), dopamine transporter (DAT), and the vesicular monoamine transporter (VMAT2) were observed 1 week after METH HCI (2x2 mg/kg; 24 h apart). Regional changes throughout the rostrocaudal extent of the striatum were characterized by a gradient of neurotoxic effect (lateral greater than medial) and the preservation of patches of IR. The decreases in IR in the caudate and putamen were greater than those in the nucleus accumbens. The reduced IR in the METH-exposed striatum allowed for the visualization of dopamine phenotype cell bodies. Within the ventral midbrain, the METH-exposed substantia nigra pars compacta (SNc) also showed a heterogeneous loss of IR (lateral greater than medial). In contrast, the ventral tegmental area (VTA) showed only minor decreases in IR. The magnitude of the decreases in the SNc and VTA subregions corresponded to those observed in their respective striatal projection areas, suggesting that nigrostriatal neuron subpopulations were differentially reactive to METH. The profile of these drug-induced nigrostriatal dopamine system deficits resembles aspects of Parkinson's disease pathology and, as such, may provide a useful model with which to evaluate neuroprotective and neurorestorative strategies.
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PMID:Regional heterogeneity of dopaminergic deficits in vervet monkey striatum and substantia nigra after methamphetamine exposure. 1095 25