Anatomy and neurotransmitters

Question 1

Parts of brainstem sup to inf

Answer 1

Midbrain
Pons
Medulla

Question 2

Function of midbrain

Answer 2

Eye movements

Primitive output for hearing and vision

Question 3

Function of pons

Answer 3

Links 2 halves of cerebellum

Coordination of eating, hearing and balance

Question 4

Function of medulla

Answer 4

Links brainstem to spinal cord

Regulates autonomic and automatic functions

Question 5

Main sulci of brain

Answer 5

Central - divides frontal and parietal
Lateral - divides temporal and frontal/parietal
Parieto-occipital

Question 6

Functions of cerebellum

Answer 6

Precise voluntary movement
Coordination
Minor cognitive function

Question 7

What is anterior and posterior to central sulcus

Answer 7

Anterior - precentral gyrus - primary motor cortex

Posterior - postcentral gyrus - primary sensory cortex

Question 8

Differences between CNS and PNS

Answer 8

PNS axons can regenerate
Myelination by Schwann cells in PNS and by oligodendrocytes in CNS
Immune response mediated by microglia in CNS which is dampened to decrease swelling
Tumours usually benign in PNS but can be either in CNS

Question 9

Where does the temporal pole lie

Answer 9

Middle cranial fossa

Question 10

What is the corpus collosum

Answer 10

Bridges 2 hemispheres of cerebrum

Question 11

Order of meninges from deep to superficial

Answer 11

Pia mater
Arachnoid mater
Meningeal dura mater
Periosteal dura mater (inner and outer skill)

Question 12

Where is the subarachnoid space

Answer 12

Between pia and arachnoid mater

Question 13

Functions of subarachnoid space

Answer 13

Contains CSF which makes brain weightless, protects the brain mechanically and provides glucose for brain

Question 14

Where is the subdural space

Answer 14

Between arachnoid and meningeal dura mater

Question 15

Where does the MMA lie

Answer 15

Between the skull and inner periosteal dura mater

Crosses the pterion

Question 16

Where are the dura venous sinuses

Answer 16

Between the meningeal and periosteal dura mater layers

Question 17

Difference between T1 and T2 MRI scans

Answer 17

T1: dark CSF
T2: light CSF

Question 18

What contrast is used for brain MRI and how does it reveal tumours

Answer 18

Gadolinium

Shows disturbances in BBB and tumours are highly vascular with a poor BBB

Question 19

What constitutes the BBB

Answer 19

Capillary endothelium
BM
End foot processes of astrocytes

Question 20

What class of cells are microglia

Answer 20

APCs

Question 21

Functions of astrocytes (5)

Answer 21

Structural support
Glucose lactate shuffle - astrocytes store glycogen to make lactate which crosses BBB to enter glycolysis 
Remove glutamate 
Remove K+ in ECF
Form BBB

Question 22

Classes of neurotransmitters and some examples of each

Answer 22

Excitatory amino acid - glutamate
Inhibitory amino acid - GABA, glycine
Biogenic amines - ACh, NA, dopamine, serotonin, histamine
Peptides - neuropeptide Y, somatostatin

Question 23

Classes of glutamate receptor

Answer 23

Ionoptropic - AMPA, NMDA

GPCR

Question 24

General consequence of ionotropic glutamate receptor activation

Answer 24

Excitatory post synaptic potential where depolarisation causes more APs

Question 25

Consequence of GPCR glutamate receptor activation

Answer 25

Decreased levels of cAMP

Question 26

How do AMPA and NMDA receptors work together

Answer 26

AMPA receptor activation by glutamate binding causes neuronal depolarisation. NMDA receptors are only activated when glutamate binds in depolarised neurones. This allows Ca influx which up regulates AMPA receptors.

Question 27

Why is glutamate toxic to neurones

Answer 27

Too much Ca influx via NMDA receptors

Question 28

General consequence of GABA and glycine binding to their receptors

Answer 28

Cl- influx leading to Inhibitory post synaptic potential where hyperpolarisation causes less APs

Question 29

Which drugs utilise GABA

Answer 29

Benzodiazepines

Question 30

What receptors does ACh act on in the brain and what effect does this have on neurones

Answer 30

Nicotinic and muscurinic | Excitation

Question 31

Where do cholinergic pathways in brain run from and to

Answer 31

Originate in nucleus basalis, forebrain and brainstem | Project to cortex and hippocampus

Question 32

Functions of cholinergic pathways in brain

Answer 32

Arousal Learning Memory Motor control

Question 33

Pathophysiology of Alzheimer's disease

Answer 33

Degeneration of cholinergic neurones in the nucleus basalis

Question 34

What are the dopaminergic pathways in the brain

Answer 34

Mesocortical Mesolimbic Nigrostriatal Tubuloinfundibular

Question 35

Where does the nigrostriatal pathway run from and to

Answer 35

Substancia nigra to the corpus striatum

Question 36

Pathophysiology of Parkinson's disease

Answer 36

Loss of dopaminergic neurones in the nigrostriatal pathway

Question 37

What receptors does NA act on in the brain

Answer 37

Alpha and beta adrenoreceptors

Question 38

Where do noradrenergic and serotonergic pathways run from and to

Answer 38

Originate from locus ceruleus, pons and medulla | Project to cortex, hypothalamus, amygdala, cerebellum