Session 2 Flashcards
What is the starting point of superior sagittal sinus?
crista galli
What aperture allows excretion of CSF into the venous sinuses
Arachnoid granulations
What are the contributors of cavernous sinus?
Superior and inferior ophthalmic, Sphenoparietal sinus, Superficial middle cranial cerebral vein
What does the sigmoid sinus becomes and at what point
IJV after crossing jugular foramen
What is the location od superficial veins of the brain?
subarachnoid space
What do veins of the spinal cord drain into?
posterior radicular vein and then into vertebral venous plexus
Name branches of vertebral arteries?
meningeal, anterior spinal (x1), posterior inferior cerebellar
Name branches of basilar arteries?
anterior inferior cerebellar, pontine and labyrinthine a. , superior cerebellar and posterior cerebral (bifurcation point)
what is the blood supply to the cerebellum
superior, anterior-inferior and posterior-inferior cerebellar arteries
What regions are supplied by posterior cerebral artery
midbrain thalamus, temporal and occipital lobe
What are the branches of ICA
ophthalmic, middle and anterior cerebral, posterior communicating, hypophyseal (pituitary portal system)
what is the territory of anterior cerebral a
frontal and parietal lobes, medial aspect
what is the territory of middle cerebral a
parietal, temporal and frontal lobes=> lateral
what is the territory of posterior cerebral a
temporal and occipital lobes and thalamus
what is the arterial blood supply to the spine
anterior and posterior spinal arteries and segmental medullary arteries (branches of aorta including artery of Adamkiewicz)
What are the characteristics of obstructed supply to anterior spinal artery?
spinal shock=> initial flaccidity, areflexia and ataxia (medical emergency). If not treated it progresses to upper motor neuron lesion related symptoms
List the parts of lateral ventricle
frontal(A), body (parietal), temporal(inferior) Occipital (P)
What are the openings of 4th ventricle
foramen of Medium and lateral foramen x2 central canal
What is the role of astrocytes?
BBB, neurotransmitter scavenging (i.e. toxic glutamate), ion concentration control (especially K during firing), nutrients/energy (lactate)
What is the role of oligodendrocytes
myelination
What is the role of microglia
immunity=> phagocytosis and antigen presenting
What is the composition of BBB
BM of capillaries, tight junction, end feet of astrocyte processes
What are the two channels activated by glutamate
AMPA and NMDA
Why are NMDA receptors special
only activated in depolarisation ( blocked by Mg) permeable to calcium. Lead to long term changes (Plasticity)
What is meant by plasticity
long term potentiation of neurons due to increase in calcium as a result of activation of glutamate NMDA and GPCRs.
How NMDA receptors may lead to cell death in stroke
spread of depolarisation leads to opening of NMDA receptors and calcium influx that may result in calcium mediated neurotoxicity
What are the functions of GABA and glycine and what is the mechanism of action?
transient chloride channel leads to hyperpolarisation and inhibition of transmission Also through Gq
Where are most of Ach receptors located in the brain
pre-synaptic, basal forebrain, brainstem, diffused through cortex and hippocampus
which major pathways is dopamine involved in
Nigrostriatal and mesolimbic and monocortical
What are the two conditions that result in disturbances of dopaminergic pathways
PD and schizophrenia
Where are most of NA receptors located in the brain
cortex, hypothalamus, amygdale, cerebellum
How are NMDA receptors activated
glutamate and depolarisation( removes Mg)
