BB EOYS3 Flashcards
Which drug is used to treat muscle spasticity in conditions such as multiple sclerosis, cerebral palsy and spinal cord injuries? [1]
Baclofen: GABA agonist
Which tract are the motor commands from the spinocerebellum are sent down?
reticulospinal tract
rubrospinal tract
corticospinal tract
corticobulbar tract
Which tract are the motor commands from the spinocerebellum are sent down?
reticulospinal tract
rubrospinal tract
corticospinal tract
corticobulbar tract
Label A&B of the closed loop of the cerebrocerebellum
A: relay nuclei
B: thalamus
What is the most common type of CNS tumour in children?
Neuroblastoma
Medulloblastoma
Glioblastoma
Schwannoma
What is the most common type of CNS tumour in children?
Neuroblastoma
Medulloblastoma
Glioblastoma
Schwannoma
Morphine has what effect after binding to Mu receptor:
Increases K+ and Ca2+
Increases K+ and decreases Ca2+
Decreases K+ and Ca2+
Decreases K+ and increases Ca2+
Morphine has what effect after binding to Mu receptor:
Increases K+ and Ca2+
Increases K+ and decreases Ca2+
Decreases K+ and Ca2+
Decreases K+ and increases Ca2+
Baclofen is an agonist to which of the following
Ca2+
AMPA glutamate receptor
Amines
GABA
NMDA Glutamate receptor
Baclofen is an agonist to which of the following
Ca2+
AMPA glutamate receptor
Amines
GABA
NMDA Glutamate receptor
Label A-E
A: Floccus
B: cerebellar tonsil
C: vermis
D: superior cerebellar peduncle
E: 4th ventricle
State if the following contain input or output fibres [3]
State where the fibres go to / come from
Superior cerebellar peduncle
Middle cerebellar peduncle
Inferior cerebellar peduncle
- Superior cerebellar peduncle has output fibres only. This is mainly going up to the motor thalamus
- Middle cerebellar peduncle (largest of the 3) contains input fibres from the contralateral cerebral cortex and cranial nerves
- Inferior cerebellar peduncle has input fibres from the spinal cord
Describe the course of the spinocerebellar tract (dorsal and ventral spinocerebellar tracts)
- first order neuron transmits sensation along the spinal nerve and travels via dorsal root in the spinal cord
- Dorsal (posterior) spinocerebellar tract: is wholly ipsilateral. Second order neuron stays on same side and enters cerebellum at inferior cerebellar peduncle on same side
- Ventral (anterior) spinocerebellar tract: is contralateral: Second order neuron crosses over, ascends and enters cerebellum where it crosses back over (terminate in the ipsilateral cerebellum.The fibres decussate twice – and so terminate in the ipsilateral cerebellum.
Name the 4 deep cerebellar nuclei [4]
What is their overall collective function? [1]
“Don’t Eat Greasy Food”
Dentate
Emboliform
Globos
Fastigial
Overall: Relay nuclei which information to the cerebellum passes through
Cerebellum function
State and describe the location of the three functional zones of the cerebellum
Also state which cerebellar nuclei related to each zone [4]
- Vestibulocerebellum comprises the flocculonodular lobe and its connections to the lateral vestibular nucleus of the pons
- Spinocerebellum comprises the anterior lobe and vermis, connected to the fastigial, globose and emboliform nuclei
- Cerebrocerebellum is comprised of the posterior lobe (cerebellar hemispheres) controlled by the dentate nucleus
State the function of the spinocerebellum [1]
Via which tract are motor commands from the spinocerebellum sent down? [1]
The spinocerebellum (anterior lobe and vermis) controls locomotion and limb coordination, and balancing your body the ground
It sends motor commands down the reticulospinal tracts to coordinate postural and locomotor movements: i.e. when you run, walk, lean over to grab something, you don’t lose balance and fall over.
(This is a more dynamic balance when compared to the vestibulocerebellum which is more of a static balance)
State the function of the cerebrocerebellum [1]
From where do the inputs for the cerebrocerebellum come from in the brain [1] & the cerebellum? [1]
From where do the outputs for the cerebrocerebellum go to in the brain [1] & the cerebellum? [1]
Which deep nuclei is involved with the cerebrocerebellum? [1]
Cerebrocerebellum: coordinates movements initiated by the motor cortex. This includes speech, voluntary movements of hands, arms, and hand-eye coordination. It is also involved in speech coordination
Input = from cerebral cortex via middle cerebellar peduncle
Output: To motor thalamus via superior cerebellar peduncle
Deep nuclei involved = dentate
What is the function of the vestibulocerebellum? [2]
- coordinates head and eye movements to ensure the stability of gaze.
- It controls balance of the head on the body via the medial vestibulospinal tract and helps balance of the body on the ground via the lateral vestibulospinal tract
Cerebellar pathologies:
Why do tumours from ependymal cells specifically compress the cerebellum? [1]
What is the name for these types of tumours? [1]
Medulloblastoma:
Tumours which grow from the ependymal cells grows in the 4th ventricle, and it tends to grow in the midline so very specifically compresses the nodulus of the cerebellum.
What is the most common type of CNS tumour in children? [1]
Medulloblastoma: tumours arising from cerebellum
What are the symptoms of flocculonodular syndrome? [3]
little control of axial muscles, wide based ataxic gait with reeling and swaying
Why do alcoholics often suffer from anterior lobe syndrome? [1]
brain needs B12 for myelin generation and the cerebellum has a higher turnover than most parts of the brain meaning it needs more, so if depleted in alcoholics it causes problems
What are the characteristics of anterior lobe syndrome? [4]
- incoordinaion of the limbs (especially legs)
- ataxic gait (walks in a wide platform so they don’t fall over, this overlaps with flocculonodular syndrome).
- hypotonia
- reflexes appear depressed or pendular (UMN lesion)
Neocerebellar syndrome occurs due to damage to which functional part of the cerebellum? [1]
What are characterisitic features of neocerebellar syndrome? [5]
Damage to the cerebrocerebellum
Characterisitc features:
* Loss of hand-eye coordination.
* Dysmetria (inaccurate reaching with intention tremor)
* Dysdiadochokinesis (the irregular performance of rapid alternating movements of the hands)
* Intention tremors occur on an attempt to touch an object
* Loss of good speech articulation/slurred speech which is due to a loss of coordination of muscles involved in speech production
Name 6 characteristics of cerebellar stroke
Dysdiadochokinesia: is the inability to perform rapid alternating muscle movements
Ataxia (gait and posture)
Nystagmus
Intention tremor
Slurred, staccato speech
Hypotonia/heel-shin test
- . Headache, vertigo, nausea, vomiting
- . Eye changes (nystagmus, ptosis)
- . Dysarthria and dysphagia (Dysarthria is a motor disorder of speech weakening the muscles of the mouth, face and respiratory system)
- . Ataxia
- . Arm weakness and incoordination
Label A & B
A: inferior cerebellar peduncle
B: Vestibular nuclei
interposed nuclei comprise the [] nucleus and the [] nucleus
interposed nuclei comprise the emboliform nucleus and the globose nucleus
Which functional zone of the cerebellum is the dentate nucleus connected to? [1]
Which areas of the brain does this tract connected to the dentate nucleus send to after connecting to the dentate nucleus? [2]
Dentate nucleus:
- Connected to cerebrocerebellum
- Sends information to the contralateral red nucleus and the ventrolateral (VL) thalamic nucleus.
The vestibulocerebellum:
Controls balance of the head on the body via the [] tract
Helps balance of the body on the ground via the [] tract
coordinates head and eye movements to ensure the stability of gaze.
It controls balance of the head on the body via the medial vestibulospinal tract
Helps balance of the body on the ground via the lateral vestibulospinal tract
Purkinje cells are GABAergic/Glutaminergic?
Purkinje cells are GABAergic
Which spinal tract sends information about nociception? [1] (be specific)
Where does the first synapse of this spinal tract occur? [1]
Lateral spinothalamic tract
First synapse is the dorsal horn at the spinal level: target for targets of pain control
Desribe the pathway of the lateral spinothalamic tract [3]
First-order neurones”
- cell bodies are in the dorsal root ganglion whose axons extend from peripheral receptors
Second-order neurones
- cross almost immediately via the anterior spinal commissure and form the lateral spinothalamic tract
- Then ascends in the lateral funiculus. Fibres of this tract are somatotopically organised for their entire course.
Third-order VPL neurons:
- send axons through the posterior limb of the internal capsule to the somatosensory cortex (areas 3, 1, 2).
How are endogneous opioids rapidly inactivated when in circulation? [1]
Peptides are rapidly inactivated by peptidases in the circulation
Explain the MoA of morphine [4]
- Mu acts on receptors (e.g. Mu)
- Causes activation of K+ conductance and decreased calcium conductance
- This leads to decreased excitability (K+) and decreased release of neurotransmitters (Ca2+).
- Inhibits cAMP formation
Asides from morphine, name 5 other opioids prescribed
- Herion: high solubility compared to morphine
- Dextromoramide: potent but limited prescription
- Methadone: large half-life - so used for long dosing.
- Meptazinol: Mu-1 produces less respiratory depression than morphine
Explain MoA of paracetamol [1]
reduces the active oxidized form of COX-2 / selective COX-2 inhibitor
tricylic anti-depressants work by inhbiting the reuptake of which of the following
Ca2+
AMPA glutamate receptor
Amines
GABA
NMDA Glutamate receptor
tricylic anti-depressants work by inhbiting the reuptake of which of the following
Amines: serotonin and norepinephrine in presynaptic terminals,
Ketamine works as an antagonist to which of the following?
Ca2+
AMPA glutamate receptor
Amines
GABA
NMDA Glutamate receptor
Ketamine works as an antagonist to which of the following?
NMDA Glutamate receptor
Baclofen is an agonist to which of the following
Ca2+
AMPA glutamate receptor
Amines
GABA
NMDA Glutamate receptor
Baclofen is an agonist to which of the following
Ca2+
AMPA glutamate receptor
Amines
GABA
NMDA Glutamate receptor
Carbamazepine, sodium valproate, pregabalin treat what type of pain? [2]
Neuropathic pain; Trigeminal neuralgia
Name a tricyclic antidepressant that is used to treaet neuropathic and cancer pain [1]
Amitriptyline
Explain the mechanism of action of tricylic anti-depressants [2]
Tricylic antidepressants inhibit the reuptake of amines (dopamine, norepinephrine, adrenaline, noradrenaline histamine, and serotonin) and also block sodium and calcium channels
Pain management for complex pain types
Describe MoA of ketamine [1]
NMDA glutamate receptor antagonist
Pain management for complex pain types
What is the MoA of baclofen? [1]
What type of pathologies is it used to treat? [2]
GABA receptor agonists
It’s used to relieve muscle spasms, cramping or tightness caused by conditions such as MS, cerebral palsy
Pain management for complex pain types
Describe the MoA of tramadol & tapentadol [2]
Opioid receptor agonist AND amine reuptake inhibition
What are the first three firstline drug classes recommended for neuropathic pain? [3]
- SNRIs (duloxetine)
- tricyclic antidepressants (amitrypyline)
- calcium channel blockers (gabapentin, pregabalin)
Local anaesthetics
Name 3 examples [3]
MoA? [1]
lignocaine, bupivacaine, prilocaine (all end in -caine)
Block Na channels
General anaesthetics
Mode of administration? [2]
Mechanism of action? [2]
Mode of administration: inhalational or intravenous
Mechanism of action: activation of inhibitory receptors or inhibition of excitatory receptors
Name some inhaled anaesthetics [2] and IV anaesthetics [2]
Inhaled: [end with -ane]
Halothane
Enflurane
Isoflurane
Nitrous oxide
Intravenous anaesthetics:
Propofol
Thiopental
Etomidate
Ketamine
Midazolam
Treatment for trigeminal neuralgia? [5]
carbamazepine (sodium channel blocker): 1st line
baclofen (GABAB agonist): 1st line if unresponsive
phenytoin (sodium channel blocker)
valproate (sodium channel blocker and other targets)
clonazepam (benzodiazepine)
