17 Basal Ganglia

Question 1

Which are the more predominant neuron in the striatum: spiny or aspiny?

Answer 1

95% are spiny neurons. They are smaller than aspiny neurons.

Question 2

What are the spines on spiny neurons for?

Answer 2

specialized for receiving terminals from other brain regions

Question 3

Which type of neuron has long axon that leaves the striatum?

Answer 3

spiny neurons are projection neurons. Aspiny neurons have short axons that do not leave striatum.

Question 4

What neurotransmitter do all spiny neurons use?

Answer 4

GABA (all), ENK (only those that project to GPe), subsance P (only those that project to GPi)

Question 5

What region do SP neurons project to?

Answer 5

GPi, SNc, and SNr

Question 6

What region to ENK neurons project to?

Answer 6

GPe (ENK for E)

Question 7

Where are substance P terminals located in substantia nigra?

Answer 7

pars compacta (upper shelf) and in region of substantia nigra below dopaminergic receptors (pars reticulata)

Question 8

Which dopamine receptor type is specific for ENK? Is it excitatory or inhibitory?

Answer 8

D2. Inhibitory

Question 9

Which dopamine receptor type is specific for SP (and dynorphin)? Is it excitatory or inhibitory?

Answer 9

D1. Excitatory

Question 10

What is the main function of straito-SNr neurons acting on D1 receptors via SP?

Answer 10

promote eye movement

Question 11

What is the main function of straito-SNc neurons acting on D1 receptors via SP?

Answer 11

regulate dopaminergic neurons

Question 12

What is the main function of striato-GPi neurons acting on D1 receptors via SP?

Answer 12

promote limb movement

Question 13

Which striatum interneuon uses GABA?

Answer 13

all except cholinergic. (parvalbuminergic, somatostatinergic, calretinergic)

Question 14

Which striatum interneuron is impervious to Huntingtons disease? What peptide do they make?

Answer 14

somatostatin internuerons.
They make neuropeptide Y (NPY)

(table later also says that calretinergic and cholinergic survive, but parvalbuminergic definitely eat shit and die)

Question 15

What is the action of cholinergic interneurons?

Answer 15

oppose DA action

Question 16

What is the action of parvalbuminergic interneurons?

Answer 16

inhibit PNs to sharpen activity

Question 17

What is major neuron type in globus pallidus?

Answer 17

large aspiny neurons

Question 18

Where does GPe project to?

Answer 18

subthalamic nucleus

Question 19

Where does GPi project to?

Answer 19

motor thalamus (made of ventral anterior nucleus and ventral lateral nucleus)

Question 20

Which brodman area does VA (ventral anterior nucleus) project to? VL?

Answer 20

area 6.

VL to area 4

Question 21

What are the three major inputs to striatum?

Answer 21

cortex, thalamus, and substantia nigra

Question 22

Where does almost all of the cerebral cortex project to?

Answer 22

striatum

Question 23

What layer are the cortical neurons that project to the striatum in?

Answer 23

layer 5 (pyramidal neurons)

Question 24

Which dopaminergic terminals are located in GPe? GPi?

Answer 24

None. Dopaminergic terminals are in caudate and putamen

Question 25

Which part of globus pallidus is invovled in direct pathway?

Answer 25

GPi

Question 26

Which part of globus pallidus is invovled in indirect pathway?

Answer 26

first GPe, which is inhibited to allow STN to promote GPi, which will then inhibit motor cortex

Question 27

What is the primary transmitter of STN (subthalamic nucleus)? excitatory or inhibitory?

Answer 27

Glutamate, excites

Question 28

What is the primary transmitter of motor thalamus ? excitatory or inhibitory?

Answer 28

glutamate, excites

Question 29

What is the primary transmitter of SN pars reticulata? excitatory or inhibitory?

Answer 29

GABA, inhibits

Question 30

What is the primary transmitter of striatum? excitatory or inhibitory?

Answer 30

GABA, inhibits