scholarly journals Altered Neuronal Firing Pattern of the Basal Ganglia Nucleus Plays a Role in Levodopa-Induced Dyskinesia in Patients with Parkinson’s Disease

2015 ◽  
Vol 9 ◽  
Author(s):  
Xiaoyu Li ◽  
Ping Zhuang ◽  
Yongjie Li
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Basal Ganglia ◽  
Firing Pattern ◽  
Neuronal Firing

scholarly journals Neuronal Entropy-Rate Feature of Entopeduncular Nucleus in Rat Model of Parkinson’s Disease

2016 ◽  
Vol 26 (02) ◽  
pp. 1550038 ◽  
Author(s):  
Olivier Darbin ◽  
Xingxing Jin ◽  
Christof Von Wrangel ◽  
Kerstin Schwabe ◽  
Atsushi Nambu ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Basal Ganglia ◽  
Normal Condition ◽  
Rat Model ◽  
Neuronal Firing ◽  
Entopeduncular Nucleus ◽  
Motor Processing ◽  
Firing Rates ◽  
Sensory Motor

The function of the nigro-striatal pathway on neuronal entropy in the basal ganglia (BG) output nucleus, i.e. the entopeduncular nucleus (EPN) was investigated in the unilaterally 6-hyroxydopamine (6-OHDA)-lesioned rat model of Parkinson’s disease (PD). In both control subjects and subjects with 6-OHDA lesion of dopamine (DA) the nigro-striatal pathway, a histological hallmark for parkinsonism, neuronal entropy in EPN was maximal in neurons with firing rates ranging between 15 and 25[Formula: see text]Hz. In 6-OHDA lesioned rats, neuronal entropy in the EPN was specifically higher in neurons with firing rates above 25[Formula: see text]Hz. Our data establishes that the nigro-striatal pathway controls neuronal entropy in motor circuitry and that the parkinsonian condition is associated with abnormal relationship between firing rate and neuronal entropy in BG output nuclei. The neuronal firing rates and entropy relationship provide putative relevant electrophysiological information to investigate the sensory-motor processing in normal condition and conditions such as movement disorders.

scholarly journals Deep Brain Stimulation Reduces Neuronal Entropy in the MPTP-Primate Model of Parkinson's Disease

2008 ◽  
Vol 100 (5) ◽  
pp. 2807-2818 ◽  
Author(s):  
Alan D. Dorval ◽  
Gary S. Russo ◽  
Takao Hashimoto ◽  
Weidong Xu ◽  
Warren M. Grill ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Basal Ganglia ◽  
Globus Pallidus ◽  
Neuronal Activity ◽  
Firing Pattern ◽  
Neuronal Firing ◽  
Motor Symptoms ◽  
Firing Rates ◽  
Frequency Stimulation ◽  
Motor Thalamus

High-frequency stimulation (HFS) of the subthalamic nucleus (STN) or internal segment of the globus pallidus is a clinically successful treatment for the motor symptoms of Parkinson's disease. However, the mechanisms by which HFS alleviates these symptoms are not understood. Whereas initial studies focused on HFS-induced changes in neuronal firing rates, recent studies suggest that changes in patterns of neuronal activity may correlate with symptom alleviation. We hypothesized that effective STN HFS reduces the disorder of neuronal firing patterns in the basal ganglia thalamic circuit, minimizing the pathological activity associated with parkinsonism. Stimulating leads were implanted in the STN of two rhesus monkeys rendered parkinsonian by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Action potentials were recorded from neurons of the internal and external globus pallidus and the motor thalamus (ventralis anterior, ventralis lateralis pars oralis, and ventralis posterior lateralis pars oralis) during HFS that reduced motor symptoms and during clinically ineffective low-frequency stimulation (LFS). Firing pattern entropy was calculated from the recorded spike times to quantify the disorder of the neuronal activity. The firing pattern entropy of neurons within each region of the pallidum and motor thalamus decreased in response to HFS ( n ≥ 18 and P ≤ 0.02 in each region), whereas firing rate changes were specific to pallidal neurons only. In response to LFS, firing rates were unchanged, but firing pattern entropy increased throughout the circuit ( n ≥ 24 and P ≤ 10−4 in each region). These data suggest that the clinical effectiveness of HFS is correlated with, and potentially mediated by, a regularization of the pattern of neuronal activity throughout the basal ganglia thalamic circuit.

scholarly journals Ion Homeostasis in Rhythmogenesis: The Interplay Between Neurons and Astroglia

Physiology ◽  
2015 ◽  
Vol 30 (5) ◽  
pp. 371-388 ◽  
Author(s):  
Aklesso Kadala ◽  
Dorly Verdier ◽  
Philippe Morquette ◽  
Arlette Kolta
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Firing Pattern ◽  
Ion Homeostasis ◽  
Neuronal Firing ◽  
Oscillatory Activity ◽  
Proper Function ◽  
Excitable Cells ◽  
Rhythmic Firing ◽  
Neuronal Functions

Proper function of all excitable cells depends on ion homeostasis. Nowhere is this more critical than in the brain where the extracellular concentration of some ions determines neurons' firing pattern and ability to encode information. Several neuronal functions depend on the ability of neurons to change their firing pattern to a rhythmic bursting pattern, whereas, in some circuits, rhythmic firing is, on the contrary, associated to pathologies like epilepsy or Parkinson's disease. In this review, we focus on the four main ions known to fluctuate during rhythmic firing: calcium, potassium, sodium, and chloride. We discuss the synergistic interactions between these elements to promote an oscillatory activity. We also review evidence supporting an important role for astrocytes in the homeostasis of each of these ions and describe mechanisms by which astrocytes may regulate neuronal firing by altering their extracellular concentrations. A particular emphasis is put on the mechanisms underlying rhythmogenesis in the circuit forming the central pattern generator (CPG) for mastication and other CPG systems. Finally, we discuss how an impairment in the ability of glial cells to maintain such homeostasis may result in pathologies like epilepsy and Parkinson's disease.

SPECT-Befunde bei Hemiparkinson-Syndrom mit 99mTc-HMPAO

1989 ◽  
Vol 28 (03) ◽  
pp. 92-94 ◽  
Author(s):  
C. Neumann ◽  
H. Baas ◽  
R. Hefner ◽  
G. Hör
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Basal Ganglia ◽  
Neuronal Activity ◽  
Tracer Uptake ◽  
The Body ◽  
99Mtc Hmpao ◽  
Do So

The symptoms of Parkinson’s disease often begin on one side of the body and continue to do so as the disease progresses. First SPECT results in 4 patients with hemiparkinsonism using 99mTc-HMPAO as perfusion marker are reported. Three patients exhibited reduced tracer uptake in the contralateral basal ganglia One patient who was under therapy for 1 year, showed a different perfusion pattern with reduced uptake in both basal ganglia. These results might indicate reduced perfusion secondary to reduced striatal neuronal activity.

scholarly journals α-Synuclein-induced dysregulation of neuronal activity contributes to murine dopamine neuron vulnerability

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Abeer Dagra ◽  
Douglas R. Miller ◽  
Min Lin ◽  
Adithya Gopinath ◽  
Fatemeh Shaerzadeh ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Neuronal Activity ◽  
Dopaminergic Neurons ◽  
Prolonged Exposure ◽  
D2 Receptor ◽  
Neuronal Firing ◽  
Dopamine Neurons ◽  
Loss Of Function ◽  
Therapeutic Implications

AbstractPathophysiological damages and loss of function of dopamine neurons precede their demise and contribute to the early phases of Parkinson’s disease. The presence of aberrant intracellular pathological inclusions of the protein α-synuclein within ventral midbrain dopaminergic neurons is one of the cardinal features of Parkinson’s disease. We employed molecular biology, electrophysiology, and live-cell imaging to investigate how excessive α-synuclein expression alters multiple characteristics of dopaminergic neuronal dynamics and dopamine transmission in cultured dopamine neurons conditionally expressing GCaMP6f. We found that overexpression of α-synuclein in mouse (male and female) dopaminergic neurons altered neuronal firing properties, calcium dynamics, dopamine release, protein expression, and morphology. Moreover, prolonged exposure to the D2 receptor agonist, quinpirole, rescues many of the alterations induced by α-synuclein overexpression. These studies demonstrate that α-synuclein dysregulation of neuronal activity contributes to the vulnerability of dopaminergic neurons and that modulation of D2 receptor activity can ameliorate the pathophysiology. These findings provide mechanistic insights into the insidious changes in dopaminergic neuronal activity and neuronal loss that characterize Parkinson’s disease progression with significant therapeutic implications.

scholarly journals Deep brain stimulation of the subthalamic nucleus reestablishes neuronal information transmission in the 6-OHDA rat model of parkinsonism

2014 ◽  
Vol 111 (10) ◽  
pp. 1949-1959 ◽  
Author(s):  
Alan D. Dorval ◽  
Warren M. Grill
Keyword(s):  
Deep Brain Stimulation ◽  
Basal Ganglia ◽  
Information Transmission ◽  
Brain Stimulation ◽  
Rat Model ◽  
Information Transfer ◽  
Firing Pattern ◽  
Signal Propagation ◽  
Neuronal Firing ◽  
Deep Brain

Pathophysiological activity of basal ganglia neurons accompanies the motor symptoms of Parkinson's disease. High-frequency (>90 Hz) deep brain stimulation (DBS) reduces parkinsonian symptoms, but the mechanisms remain unclear. We hypothesize that parkinsonism-associated electrophysiological changes constitute an increase in neuronal firing pattern disorder and a concomitant decrease in information transmission through the ventral basal ganglia, and that effective DBS alleviates symptoms by decreasing neuronal disorder while simultaneously increasing information transfer through the same regions. We tested these hypotheses in the freely behaving, 6-hydroxydopamine-lesioned rat model of hemiparkinsonism. Following the onset of parkinsonism, mean neuronal firing rates were unchanged, despite a significant increase in firing pattern disorder (i.e., neuronal entropy), in both the globus pallidus and substantia nigra pars reticulata. This increase in neuronal entropy was reversed by symptom-alleviating DBS. Whereas increases in signal entropy are most commonly indicative of similar increases in information transmission, directed information through both regions was substantially reduced (>70%) following the onset of parkinsonism. Again, this decrease in information transmission was partially reversed by DBS. Together, these results suggest that the parkinsonian basal ganglia are rife with entropic activity and incapable of functional information transmission. Furthermore, they indicate that symptom-alleviating DBS works by lowering the entropic noise floor, enabling more information-rich signal propagation. In this view, the symptoms of parkinsonism may be more a default mode, normally overridden by healthy basal ganglia information. When that information is abolished by parkinsonian pathophysiology, hypokinetic symptoms emerge.

scholarly journals Corticostriatal Plastic Changes in Experimental L-DOPA-Induced Dyskinesia

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Veronica Ghiglieri ◽  
Vincenza Bagetta ◽  
Valentina Pendolino ◽  
Barbara Picconi ◽  
Paolo Calabresi
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Basal Ganglia ◽  
Experimental Models ◽  
Striatal Neurons ◽  
Da Receptors ◽  
Electrophysiological Studies ◽  
Plastic Changes ◽  
Stimulation Of

In Parkinson’s disease (PD), alteration of dopamine- (DA-) dependent striatal functions and pulsatile stimulation of DA receptors caused by the discontinuous administration of levodopa (L-DOPA) lead to a complex cascade of events affecting the postsynaptic striatal neurons that might account for the appearance of L-DOPA-induced dyskinesia (LID). Experimental models of LID have been widely used and extensively characterized in rodents and electrophysiological studies provided remarkable insights into the inner mechanisms underlying L-DOPA-induced corticostriatal plastic changes. Here we provide an overview of recent findings that represent a further step into the comprehension of mechanisms underlying maladaptive changes of basal ganglia functions in response to L-DOPA and associated to development of LID.

The effect of striatal pre-enkephalin overexpression in the basal ganglia of the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine mouse model of Parkinson's disease

2014 ◽  
Vol 40 (2) ◽  
pp. 2406-2416 ◽  
Author(s):  
Stéphanie Bissonnette ◽  
Sophie Muratot ◽  
Nathalie Vernoux ◽  
François Bezeau ◽  
Frédéric Calon ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Basal Ganglia ◽  
Mouse Model
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