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

OBJECTIVE: The purpose of this study is to investigate the effect of ipsilateral subthalamic nucleus(STN) lesioning on the spontaneous behavioral changes and the alteration of neuronal activities of deep cerebral nuclei in the rat parkinsonian model with 6-hydroxydopamine(6-OHDA). METHODS: To identify the spontaneous behavioral changes, apomorphine-induced rotational test and forepaw adjusting step were performed. We subsequently investigated the alteration of neuronal activities in the substantia nigra pars reticulata(SNpr) and globus pallidus(GP), in order to compare them with the behavioral changes in rat parkinsonian models. RESULTS: The STN lesioning in the rat parkinsonian model clearly improved behavioral changes. Compared to the normal control rats, rat PD models exhibited a significant increase in mean firing rates and the percentage of bursting neurons in the STN and SNpr. In the STN-lesioned rat PD models, mean firing rates and the percentage of bursting neurons in the SNpr were reduced and those in the GP increased. CONCLUSION: STN lesioning induced behavior improvement in rat parkinsonian models seems to be consistent with the surgical outcomes of the STN stimulation therapy in advanced Parkinsonn's disease(PD). The alteration of the neuronal activities in the SNpr and GP suggests that these sites are responsible for the improvement of parkinsonian motor symptoms observed following STN lesioning in rat parkinsonian models. The significance of bursting activity in the SNpr and GP remains obscure. Further study is necessary to elucidate the pathophysiological mechanism of PD.
Animals ; Fires ; Globus Pallidus ; Kainic Acid* ; Neurons* ; Oxidopamine* ; Parkinson Disease ; Rats* ; Substantia Nigra ; Subthalamic Nucleus

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*

An apomorphine-induced rotational test has been used in the evaluation of rat parkinsonian models lesioned with neurotoxin 6-hydroxydopamine (6-OHDA). Previous parkinsonian rat models have generally been characterized by unilateral destruction of both nigrosriatal pathway and mesolimbic pathway using 6-OHDA. The authors created partial lesioned rat parkinsonian models using 6-OHDA in which there is destruction of the dopaminergic nigrostriatal pathway and sparing of the mesolimbic pathway. Rats with unilateral lesions of the substantia nigra pars compacta(SNpc) were tested for rotational asymmetry using a cylindrical rotometer device with flat bottom(diameter, 30.5cm) after administration of apomorphine. After completion of the rotation test, the animals were sacrificed and their brains were immunolabeled for tyrosine hydroxylase(TH). Analysis of anatomical and behavioral data suggests that the pattern of rotation(pivotal rotation) is more reliable index for loss of TH-immunoreactive neurons in lesioned SNpc than the total number of rotational responses to apomorphine. The exact cause of the abnormal ipsiversive rotation which some rats showed is unclear. Further research should be pursued to explain this finding.
Animals ; Apomorphine ; Brain ; Models, Animal ; Neurons ; Oxidopamine* ; Parkinson Disease ; Rats* ; Substantia Nigra ; Tyrosine

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