BB EOYS1 Flashcards
Label A-C [3]
A: subthalamic nuclei
B: substantia nigra
C: thalamus
(sub is on top)
Which supplies the majority of the blood to the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the majority of the blood to the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the medial portion of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the medial portion of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the anterior and inferior of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the anterior and inferior of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the superior and posterior of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
Which supplies the superior and posterior of the globus pallidus?
anterior choroidal artery (AChA)
middle cerebral artery (MCA)
anterior cerebral artery (ACA).
posterior cererbral artrey (PCA)
lenticulostriate artery
A 65-year-old man was brought by his daughter to his provider due to tremors and increasing stiffness in both arms and legs. This has led the patient to fall twice while attempting to turn. On examination, the patient had increased muscle tone, resting tremors, and difficulty initiating movements when asked to move. A single-photon emission computed tomography (SPECT) was done, showing reduced uptake in the striatum. How would this reduced uptake affect the pathways?
A. It reduces inhibitory signals projected to the subthalamus.
B. It increases inhibitory signals projected to the subthalamus.
C. It reduces the stores of neurotransmitters present in the globus pallidus externus.
D. It increases inhibitory signals projected to the substantia nigra pars reticularis.
A 65-year-old man was brought by his daughter to his provider due to tremors and increasing stiffness in both arms and legs. This has led the patient to fall twice while attempting to turn. On examination, the patient had increased muscle tone, resting tremors, and difficulty initiating movements when asked to move. A single-photon emission computed tomography (SPECT) was done, showing reduced uptake in the striatum. How would this reduced uptake affect the pathways?
A. It reduces inhibitory signals projected to the subthalamus.
B. It increases inhibitory signals projected to the subthalamus.
C. It reduces the stores of neurotransmitters present in the globus pallidus externus.
D. It increases inhibitory signals projected to the substantia nigra pars reticularis.
Which of the following outputs to the superior colliculi?
globus pallidus external
globus pallidus internal
substantia nigra, pars reticula
subthalamic nuclei
Which of the following outputs to the superior colliculi?
globus pallidus external
globus pallidus internal
substantia nigra, pars reticula
subthalamic nuclei
What is the most common type of tremor in PD? [1]
pill-rolling’ rest tremor; looks like you are trying to roll a pill between your thumb and index
What are the functions of the basal ganlia? [4]
Regulating movement:
* Play a critical role in movement initiation
* Allow switching between motor programs (e.g. stop or start a movement)
* Inhibit antagonistic and unnecessary movements
* Regulate movement force
Label A-F
A: caudate nucleus
B: putamen
C: Globus pallidus external
D: Globus pallidus internux
E: Subthalamic nucleus
F: Substantia nigra (SN)
Which part of the basal ganglia are the input [1] and output zones [3]?
Input zones:
* Dorsal striatum (caudate nucleus & putamen)
Output zones:
* globus pallidus external
* globus pallidus internal
* substantia nigra, pars reticula (SNr)
Basal ganglia input zones:
Where do the caudate nucleus and putamen have fibres inputing into / orginating from? [3]
- Cerebral cortex - specifically the frontal cortex: primary motor cortex and parietal cortex: primary somatosensory cortex
- substantia nigra pars compacta (from the midbrain)
- Local circuit neurons within the corpus striatum (GABAergic)
Where do the following output zones of the basal ganglia send information to?
globus pallidus external (GPe) [1]
globus pallidus internal (GPi) [1]
substantia nigra, pars reticula (SNr) [1]
globus pallidus external (GPe): subthalamic nucleus
globus pallidus internal (GPi): ventral anterior (VA) / Ventrolateral (VL) thalamic nuclear complex
substantia nigra, pars reticula (SNr): superior colliculi
Neurons from substantia nigra pars reticula (SNr) synapse onto neurons in the []
Neurons from substantia nigra pars reticula (SNr) synapse onto neurons in the superior colliculus (midbrain)
Describe the indirect pathway of the dorsal ganglia
Excitation of dorsal striatum causes the release of dorsal striatum GABA (inhibitory)
This causes projects onto globus pallidus external segment: causes increased inhibition of GPe
This causes the globus pallidus external segment to release inhibitory GABA onto the subthalamic nucleus: causes reduced inhibition of STN
This causes the subthalamic nucleus to release inhibitory GABA onto the globus pallidus internal segment: which increases the activation of GPi
This causes the globus pallidus internal segment to release inhibitory GABA onto the motor thalamus: which creates increased inhibition of motor thalamus
OVERALL DEACTIVATION OF MOTOR THALAMUS -> decreased motor cortex activation.
NO GO pathway.
Describe how the hyperdirect pathway occurs
Signal from the pre-supplementory motor cortex bypasses the dorsal striatum and causes the release of glutamate (excitatory) onto subthalamic nuclei
This causes activation of subthalamic nuclei, which releases glutamate onto the GPi
Activation of GPi causes release of GABA (inhibitory) to the VA VL thalamus - which stops motor cortex
Name the two receptors found in dorsal striatum that activated by neurons from the substantia nigra
substantia nigra has neurons that activate D1 or D2 receptors on dorsal striatum
Describe the effect of the activation of the D2 dopaminergic receptors
The D2 dopaminergic receptor activated:
- decreases cAMP
- Decreaes the sensitivity of striatal GABA neurons to glutamate (makes the glutatemate LESS EXCITABLE)
- Causes increased inhibition of the sub-thalamic nucleus
- This means get increaed inhibition of the GPi
- This causes less inhibition of the VL / VA
End result: INCREASED MOTOR ACTIVITY
Explain pathophysiology of Parkinsons disease [2]
-Loss of dopaminergic neurons in the substantia nigra, which project to and innervate the dorsal striatum.
- Less D1 and D2 activation
- The indirect pathway is therefore faciliated and becomes dominant
Name the 3 classic symptoms of Parkinsons disease [3]
bradykinesia, tremor and rigidity.
Name the symptoms of HD [4]
chorea - movement disorder that causes sudden, unintended, and uncontrollable jerky movements of the arms, legs, and facial muscles.
personality changes (e.g. irritability, apathy, depression) and intellectual impairment
dystonia
saccadic eye movements - abruptly change the point of fixation.
Describe what ballismus and Athetosis are [2] and what they’re caused by [2]
Athetosis:
* slow, involuntary regular writhing movements of the fingers, hands, toes and feet (in some cases, arms, legs, neck and tongue
* Lesions to the striatum; often a result of cerebral palsy
Ballismus:
* a type of chorea, usually involving violent, involuntary flinging of one arm and/or one leg (usually one side of the body is affected: Hemiballismus). The movements are wider and more intense than chorea
* Damage to subthalamic nucleus
What is the name for this symptom?
Lesions to which region causes this symptom?
Subthalamic nuclei
Substantia nigra
Pre supplementary motor area
Lentiform nucleus
Dorsal striatum
athetosis
Lesions to which region causes this symptom?
Subthalamic nuclei
Substantia nigra
Pre supplementary motor area
Lentiform nucleus
Dorsal striatum
What is the name for this symptom?
Lesions to which region causes this symptom?
Subthalamic nuclei
Substantia nigra
Pre supplementary motor area
Lentiform nucleus
Dorsal striatum
Ballismus
Subthalamic nuclei
Substantia nigra
Pre supplementary motor area
Lentiform nucleus
Dorsal striatum
alpha-synuclein is endocded by which gene
PARK7
SNCA
LRRK2
PRKN
alpha-synuclein is endocded by which gene
PARK7
SNCA
LRRK2
PRKN
Which mitochondrial metabolite is toxic to dopaminergic pathways? [1]
MPP+
MPP+ is disruptive to
complex I of the mitochondrial respiratory chain
complex II of the mitochondrial respiratory chain
complex III of the mitochondrial respiratory chain
complex IV of the mitochondrial respiratory chain
MPP+ is disruptive to
complex I of the mitochondrial respiratory chain
complex II of the mitochondrial respiratory chain
complex III of the mitochondrial respiratory chain
complex IV of the mitochondrial respiratory chain
What is the name for the scoring scales used for disability associated with PD? [1]
What is difference between 0% and 100%? [1]
Schwab and England Activities of Daily Living
0%: Vegetative functions
100%: Completely independent - can do chorse without slowness, difficulity or impairment
The genetic link between familial PD is due to a link between which protein? [1] Which gene codes for this protein? [1]
Is PD genetic or environmental? [1]
genetic link with the protein alpha-synuclein coded by SNCA (duplications or triplications cause autosomal dominant familial PD)
disease emergence may be due to interactions environment x genes
Describe the link between mitochondrial toxicity and dopaminergic neurons [1]
What process is diruspted as a result of ^ [1]
The compound MPTP is a toxin which can be transformed into the metabolite MPP+ which is neurotoxic for dopaminergic neurons
Dysfunction of complex I of the mitochondrial respiratory chain
can lead to increased oxidative stress
Describe the mechanism of creation of dopamine [3]
L-tyrosine –> L-Dopa (Decarboxylated to create..) –> Dopamine
Describe the mechanism of dopamine metabolism [3]
Dopamine –> DOPAC –> Homovanillic acid
Dopamine binds to which two receptors? [2]
What are the subtypes of these receptors? [5]
D1-like Family Receptors:
* D1 & D5 subtypes
D2-like Family Receptors
* D2, D3 & D4 subtypes
