Author response: Motor cortex can directly drive the globus pallidus neurons in a projection neuron type-dependent manner in the rat

The basal ganglia are critical for the control of motor behaviors and for reinforcement learning. Here, we demonstrate in rats that primary and secondary motor areas (M1 and M2) make functional synaptic connections in the globus pallidus (GP), not usually thought of as an input site of the basal ganglia. Morphological observation revealed that the density of axonal boutons from motor cortices in the GP was 47% and 78% of that in the subthalamic nucleus (STN) from M1 and M2, respectively. Cortical excitation of GP neurons was comparable to that of STN neurons in slice preparations. FoxP2-expressing arkypallidal neurons were preferentially innervated by the motor cortex. The connection probability of cortico-pallidal innervation was higher for M2 than M1. These results suggest that cortico-pallidal innervation is an additional excitatory input to the basal ganglia, and that it can affect behaviors via the cortex-basal ganglia-thalamus motor loop.

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Motor cortex can directly drive the globus pallidal neurons in a projection neuron type dependent manner in rat

10.1101/677377 ◽

2019 ◽

Cited By ~ 2

Author(s):

Fuyuki Karube ◽

Susumu Takahashi ◽

Kenta Kobayashi ◽

Fumino Fujiyama

Keyword(s):

Basal Ganglia ◽

Motor Cortex ◽

Morphological Analysis ◽

Projection Neuron ◽

Excitatory Input ◽

Morphological Observation ◽

Dependent Manner ◽

Synaptic Connections ◽

Motor Behaviors ◽

Cortical Excitation

AbstractThe basal ganglia (BG) are critical for the control of motor behaviors and for reinforcement learning. Here, we demonstrate in rats that primary and secondary motor areas (M1 and M2) make functional synaptic connections in the globus pallidus (GP), not usually thought of as an input site of the BG using optogenetics and morphological analysis. The cortical excitation in the GP was as strong as that in the STN. GP neurons projecting to the striatum were preferentially innervated by the motor cortex. Morphological observation revealed that the density of axonal boutons from motor cortices in the GP was approximately 30% of that in the striatum, but was comparable to that in the STN. M1 and M2 projected differentially to the BG in terms of topography and substructures. These results suggest that cortico-pallidal innervation is an additional excitatory input to the BG, and can affects behaviors via the cortex-basal ganglia-thalamus loop.

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Author response for "Evolution of the speech‐ready brain: The voice/jaw connection in the human motor cortex"

10.1002/cne.24997/v2/response1 ◽

2020 ◽

Author(s):

Steven Brown ◽

Ye Yuan ◽

Michel Belyk

Keyword(s):

Motor Cortex ◽

Author Response ◽

Human Motor Cortex ◽

Human Motor ◽

The Voice

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The K+-evoked release of [3H]acetylcholine from slices of rat globus pallidus: modulation by δ-opioid receptors

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y91-063 ◽

1991 ◽

Vol 69 (3) ◽

pp. 414-418 ◽

Cited By ~ 2

Author(s):

Bianca B. Ruzicka ◽

Khem Jhamandas

Keyword(s):

Globus Pallidus ◽

Opioid Receptor ◽

Opioid Receptors ◽

Cholinergic Neurons ◽

Receptor Activation ◽

Inhibitory Effect ◽

Dependent Manner ◽

Release Of Acetylcholine ◽

Δ Opioid Receptor ◽

Tritium Release

Previous investigations have shown that the activation of δ-opioid receptors depresses the release of acetylcholine (ACh) in the rat caudate putamen. This finding raised the possibility that the release of ACh is similarly modulated in the globus pallidus, a region containing a distinct population of cholinergic neurons and enriched in enkephalinergic nerve terminals. In the present study the pallidal release of ACh was characterized and the effects of δ-opioid receptor activation on this release were examined. The results show that this release is stimulated by high K+ in a concentration- and Ca2+-dependent manner. D-Pen2,L-Pen5-enkephalin (0.1 – 10 μM), a selective δ-opioid receptor agonist, produced a dose-related inhibition of the 25 mM K+-evoked tritium release. The maximal inhibitory effect, representing a 34% decrease in the K+-induced tritium release, was observed at a concentration of 1 μM. This opioid effect was attenuated by the selective δ-opioid receptor antagonist, ICI 174864 (1 μM). These findings support the role of a δ-opioid receptor in the modulation of ACh release in the rat globus pallidus.Key words: globus pallidus, acetylcholine, enkephalin, release.

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Spinal cord representation of motor cortex plasticity reflects corticospinal tract LTP

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2113192118 ◽

2021 ◽

Vol 118 (52) ◽

pp. e2113192118

Author(s):

Alzahraa Amer ◽

Jianxun Xia ◽

Michael Smith ◽

John H. Martin

Keyword(s):

Spinal Cord ◽

Motor Cortex ◽

Corticospinal Tract ◽

Cervical Spinal Cord ◽

Long Term Potentiation ◽

Dependent Manner ◽

Term Potentiation ◽

Spinal Cord Segment ◽

Spinal Interneuron ◽

Activity Dependent

Although it is well known that activity-dependent motor cortex (MCX) plasticity produces long-term potentiation (LTP) of local cortical circuits, leading to enhanced muscle function, the effects on the corticospinal projection to spinal neurons has not yet been thoroughly studied. Here, we investigate a spinal locus for corticospinal tract (CST) plasticity in anesthetized rats using multichannel recording of motor-evoked, intraspinal local field potentials (LFPs) at the sixth cervical spinal cord segment. We produced LTP by intermittent theta burst electrical stimulation (iTBS) of the wrist area of MCX. Approximately 3 min of MCX iTBS potentiated the monosynaptic excitatory LFP recorded within the CST termination field in the dorsal horn and intermediate zone for at least 15 min after stimulation. Ventrolaterally, in the spinal cord gray matter, which is outside the CST termination field in rats, iTBS potentiated an oligosynaptic negative LFP that was localized to the wrist muscle motor pool. Spinal LTP remained robust, despite pharmacological blockade of iTBS-induced LTP within MCX using MK801, showing that activity-dependent spinal plasticity can be induced without concurrent MCX LTP. Pyramidal tract iTBS, which preferentially activates the CST, also produced significant spinal LTP, indicating the capacity for plasticity at the CST–spinal interneuron synapse. Our findings show CST monosynaptic LTP in spinal interneurons and demonstrate that spinal premotor circuits are capable of further modifying descending MCX control signals in an activity-dependent manner.

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