Article

Functional connectivity and integrative properties of globus pallidus neurons.

Department of Biology, Emory University, Atlanta, GA 30322, USA.
Neuroscience (impact factor: 3.38). 07/2011; 198:44-53. DOI:10.1016/j.neuroscience.2011.07.050 pp.44-53
Source: PubMed

ABSTRACT The globus pallidus consists of the external (GPe) and the internal (GPi) segments. The GPe and GPi have different functional roles. The GPe is located centrally within multiple basal ganglia feedforward and feedback connections. The GPi is an output nucleus of the basal ganglia. A complex interplay between intrinsic pacemaking conductances and the balance of glutamatergic and GABAergic input largely determines the rate and pattern of firing of pallidal neurons. The initial part of this article introduces recent findings made in vivo that are related to the roles of glutamatergic and GABAergic inputs in the control of pallidal activity. The latter part describes the roles of intrinsic mechanisms of GPe neurons in the integration of the synaptic inputs. The presence of dendritic voltage-gated sodium channels may allow the initiation of dendritic spikes, giving distal inputs on the long and thin GPe dendrites an opportunity to strongly shape spiking activity. Basal ganglia disorders including Parkinson's disease, hemiballismus, and dystonias are accompanied by increased irregularity and synchronized bursts of pallidal activity. These changes may be in part due to changes in the GABA release in the GPe and GPi, but also involve intrinsic cellular changes in pallidal neurons.

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Keywords

article introduces recent findings
 
Basal ganglia disorders
 
complex interplay
 
dendritic voltage-gated sodium channels
 
distal inputs
 
GABA release
 
GABAergic input
 
GABAergic inputs
 
globus pallidus
 
GPe neurons
 
intrinsic cellular changes
 
intrinsic mechanisms
 
intrinsic pacemaking conductances
 
multiple basal ganglia feedforward
 
output nucleus
 
pallidal activity
 
pallidal neurons
 
shape spiking activity
 
synaptic inputs
 
thin GPe dendrites
 

D Jaeger