Corpus Striatum ; Dopaminergic Neurons ; Humans ; Mesencephalon ; Parkinson Disease/drug therapy* ; Pars Compacta ; Substantia Nigra

No abstract available.
Animals ; Neurons* ; Oxidopamine* ; Rats* ; Substantia Nigra*

No abstract available.
Animals ; Immunohistochemistry* ; Neurons* ; Rats* ; Substantia Nigra*

Parkinson disease (PD) is a neurodegenerative disease characterized by the selective loss of dopaminergic neurons from the substantia nigra pars compacta leading to the impairment of motor functions. Recent genetic studies have uncovered several genes involved in inherited forms of the disease. These gene products are likely to be implicated in the biochemical pathways underlying the etiology of sporadic PD. Our review discusses the pathogenetic mechanisms of the mutated genes.
Dopaminergic Neurons ; Genetics ; Neurodegenerative Diseases ; Parkinson Disease* ; Substantia Nigra

BACKGROUND: Quantitative susceptibility mapping (QSM) has been used to measure iron accumulation in the deep nuclei of patients with Parkinson's disease (PD). This study examined the relationship between non-motor symptoms (NMSs) and iron accumulation in the deep nuclei of patients with PD. METHODS: The QSM data were acquired from 3-Tesla magnetic resonance imaging (MRI) in 29 patients with early PD and 19 normal controls. The Korean version of the NMS scale (K-NMSS) was used for evaluation of NMSs in patients. The patients were divided into high NMS and low NMS groups. The region-of-interest analyses were performed in the following deep nuclei: red nucleus, substantia nigra pars compacta, substantia nigra pars reticulata, dentate nucleus, globus pallidus, putamen, and head of the caudate nucleus. RESULTS: Thirteen patients had high NMS scores (total K-NMSS score, mean = 32.1), and 16 had low NMS scores (10.6). The QSM values in the deep were not different among the patients with high NMS scores, low NMS scores, and controls. The QSM values were not correlated linearly with K-NMSS total score after adjusting the age at acquisition of brain MRI. CONCLUSION: The study demonstrated that the NMS burdens are not associated with iron accumulation in the deep nuclei of patients with PD. These results suggest that future neuroimaging studies on the pathology of NMSs in PD should use more specific and detailed clinical tools and recruit PD patients with severe NMSs.
Basal Ganglia ; Brain ; Caudate Nucleus ; Cerebellar Nuclei ; Globus Pallidus ; Head ; Humans ; Iron* ; Magnetic Resonance Imaging ; Neuroimaging ; Parkinson Disease* ; Pars Compacta ; Pars Reticulata ; Pathology ; Putamen ; Red Nucleus

The aim of this study was to examine the effects of various concentrations of glutamate(10(-8), 10(-6) and 10(-4) M) on the circling movement induced by apomorphine in the unilateral substantia nigra-lesioned rats. Subcutaneous apomorphine(0.1 mg/kg) elicited contralateral circling movement(641.7+/-163.9/hr), Glutamate(10(-6)-10(-4) M) significantly reduced the numbers of apomorphine-induced circling movement. This reducing effect of glutamate was antagonized and/or reversed by 10(-7) M GABA antagonist bicuculline. These results suggest that glutamate reduces circling movement induced by apomorphine and this reducing effect of glutamate may be mediated by increased GABA concentration in striatum and substantia nigra.
Animals ; Apomorphine ; Bicuculline ; Dopamine ; GABA Antagonists ; gamma-Aminobutyric Acid ; Glutamic Acid* ; Rats* ; Substantia Nigra

BACKGROUND AND PURPOSE: Previous T2 relaxometry studies have provided evidence for regional brain iron deficiency in patients with restless legs syndrome (RLS). Measurement of the iron content in several brain regions, and in particular the substantia nigra (SN), in early- and late-onset RLS patients using T2 relaxometry have yielded inconsistent results. In this study the regional iron content was assessed in patients with early- and late-onset RLS using magnetic resonance imaging (MRI), and compared the results with those in controls. METHODS: Thirty-seven patients with idiopathic RLS (20 with early onset and 17 with late onset) and 40 control subjects were studied using a 3.0-tesla MRI with a gradient-echo sampling of free induction decay and echo pulse sequence. The regions of interest in the brain were measured independently by two trained analysts using software known as medical image processing, analysis, and visualization. The results were compared and a correlation analysis was conducted to investigate which brain areas were related to RLS clinical variables. RESULTS: The iron index in the SN was significantly lower in patients with late-onset RLS than in controls (p=0.034), while in patients with early-onset RLS there was no significant difference. There was no significant correlation between the SN iron index of the late-onset RLS group and clinical variables such as disease severity. CONCLUSIONS: Late-onset RLS is associated with decreased iron content in the SN. This finding supports the hypothesis that regional brain iron deficiency plays a role in the pathophysiology of late-onset RLS.
Brain* ; Humans ; Iron ; Magnetic Resonance Imaging* ; Red Nucleus ; Restless Legs Syndrome* ; Substantia Nigra

It is suggested that calbindin buffers the concentration of intracellular calcium as the calcium binding protein in the cell. In the neurodegerative disease such as Parkinsonian disease, Huntington 'disease, Alzheimer 'disease there is some change of calbindin. The calcium mediated neurotoxicity begins due to the decrease of calbindin gene in those disease. In this study the substantia nigra of the normal rat is immunostained with anti -calbindin antibody, the morphological characteristics and distribution of calbindin positive neurons are studied to confirm the suggestive neuroprotective role of calbindin in the Parkinsonian disease. In the substantia nigra tissues of rats, calbindin was immunostained in the cell body and cellular processes of the polygonal or ovoid neurons. The calbindin immumostained neurons were distributed mainly in the substantia nigra lateralis than substantia nigra compacta and have even distribution from cephalic section to caudal section. The degree of calbindin -immunostaining was similar from medial area to lateral area, from ventral area to dorsal area in the one section of substantia nigra. These results support the potentiative neuroprotective role of calbindin in the Parkinsonian disease.
Animals ; Buffers ; Calbindins* ; Calcium ; Carrier Proteins ; Immunohistochemistry ; Neurons* ; Rats* ; Substantia Nigra*

BACKGROUND: Many recent studies based on non-linearity have been performed to quantify the complex behavior of the brain in order to understand the pathophysiology of Parkinson's disease (PD). METHODS: We calculated the Fractal dimension (FD) and Lyapunov exponent (L1), the non-linear biologic signals, by digital EEG using 'CHASIM' program, non-linear times series signal simulator and then compared the UPDRS score with the degree of atrophy in the substantia nigra upon brain MRI and EEG data respectively. All subjects (N=20) showed definite hemiparkinsonism. RESULTS: Upon EEG analysis, a strong positive correlation was noted between FD of the left hemispheric electrodes (FP1,F3,T3,T5) and the UPDRS scores in left-sided symptomatic patients. Additionally, positive correlations were noted between the ipsilateral MRI index ratio in the right and left-sided symptomatic patients and respective UPDRS scores. CONCLUSIONS: These results suggested that thalamocortical drive is reduced in the contralateral hemisphere to parkinsonian symptoms and thalamocortical or corticothalamic glutaminergic projection in the ipsilateral hemisphere is increased in the early stage of Parkinson's disease. Additionally, hemiparkinsonim may primarilly cause anatomic and functional changes in the contralateral hemisphere and a compensatory effect in the ipsilateral hemisphere at the same time. We suggest that disease duration may be a compensating factor and of which require further investigation. We hope that our results will aid the understanding of the specific patterns of dysfunction and treatment effects by non-linear EEG measures and anatomic changes of the substantia nigra through continuous follow up of the patients. (J Korean Neurol Assoc 19(3):232~238, 2001)
Atrophy ; Brain ; Electrodes ; Electroencephalography* ; Fractals ; Hope ; Humans ; Magnetic Resonance Imaging ; Parkinson Disease* ; Substantia Nigra

BACKGROUND: Apomorphine-induced rotational behavior of unilateral 6-hydroxydopamine (OHDA) lesioned rat is widely used to develop anti-Parkinsonian treatments including drugs, neuroprotective therapy, and neural graft. Time course of changes in rotational behavior after lesioning, however, has not been fully elucidated. The aim of this study was to observe the chronological changes in the rotational response and to find the optimal period when this model is used for investigation of various therapies. METHODS: 6-OHDA was stereotaxically delivered to the unilateral substantia nigra in 13 rats. Rotational responses to apomorphine administrations were counted in the rotomotor on 2, 4, 8, 12, and 14 weeks after lesioning. RESULTS: The total turns for two hours increased continuously up to eight weeks, and then plateaued. CONCLUSIONS: Apomorphine-induced rotations increase until eight weeks after 6-OHDA lesioning. Therefore, this Parkinsonian model should be used at least eight weeks after lesioning. Even though priming was not excluded as an explanation in the experiment, we reason that progressive degeneration of dopaminergic neurons may explain the chronological changes in rotational behavior.
Animals ; Apomorphine* ; Dopaminergic Neurons ; Neuroprotective Agents ; Oxidopamine* ; Rats* ; Substantia Nigra ; Transplants