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

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

Hallervorden-Spatz disease is a rare, autosomal recessive disorder of mainly early childhood which is characterized by pigmentary degeneration of the globus pallidus, substantia nigra, and red nucleus. Clinically it manifests various symptoms and signs of extrapyramidal and pyramidal involvement. Authors report a 28-year-old female patient with suspected Hallervorden-Spatz disease in the aspects of clinical and MRI findings suggesting metal deposition in the globus pallidus, substantia nigra, and red nucleus on both side.
Adult ; Female ; Globus Pallidus ; Humans ; Magnetic Resonance Imaging ; Pantothenate Kinase-Associated Neurodegeneration* ; Red Nucleus ; 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

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

Although secondary delayed neuronal death has been considered as a therapeutic target to minimize brain damage induced by several injuries, delayed neuronal death does not occur always. In this study, we investigated possible mechanisms that prevent delayed neuronal death in the ATP-injected substantia nigra (SN) and cortex, where delayed neuronal death does not occur. In both the SN and cortex, ATP rapidly induced death of the neurons and astrocytes in the injection core area within 3 h, and the astrocytes in the penumbra region became hypertropic and rapidly surrounded the damaged areas. It was observed that the neurons survived for up to 1-3 months in the area where the astrocytes became hypertropic. The damaged areas of astrocytes gradually reduced at 3 days, 7 days, and 1-3 months. Astrocyte proliferation was detectable at 3-7 days, and vimentin was expressed in astrocytes that surrounded and/or protruded into the damaged sites. The NeuN-positive cells also reappeared in the injury sites where astrocytes reappeared. Taken together, these results suggest that astroycte survival and/or gliosis in the injured brain may be critical for neuronal survival and may prevent delayed neuronal death in the injured brain.
Adenosine Triphosphate ; Astrocytes ; Brain Injuries ; Brain* ; Gliosis ; Neurons* ; Substantia Nigra ; Vimentin

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