internal carotid artery - ANSWER Name this artery.
anterior cerebral artery - top is A2, bottom is A1
A1 - supplies internal capsule, limbic system; may have minimal Sx d/t collateral flow
from ACoA
A2 - contralateral paresis and anesthesia of lower limb - ANSWER Name this artery and
its segments.
Name the stroke symptoms associated with occlusion of each segment.
middle cerebral artery - M1 is proximal to the early cortical branches and M2 is distal to
the early cortical branches
either segment - contralateral hemiplegia, hemianesthesia, homonymous hemianopia
Dominent hemisphere = Dysarthria (actually aphasia)
Nondominent = Neglect - ANSWER Name this artery and its segments.
Name the stroke symptoms associated with occlusion of each segment.
posterior cerebral artery - P1 is proximal to PCoA, P2 is distal to PCoA.
P1 Syndrome - affects midbrain, thalamus, hypothalamus. Claude syndrome - third
nerve palsy and contralateral ataxia (red nucleus of midbrain); Weber's syndrome - third
nerve palsy and hemiplegia (cerebral peduncle)
P2 Syndrome - affects medial temporal and occipital lobes. Contralateral homonymous
hemianopia with macular sparing. - ANSWER Name this artery and its segments.
Name the stroke symptoms associated with occlusion of each segment.
basilar artery
"Locked in" syndrome - quadreplegia, cranial nerve signs, preserved consciousness
(lower midbrain) - ANSWER Name this artery. Name the stroke symptoms associated
with occlusion of this artery.
pontine arteries - ANSWER #11 - name the arteries
superior cerebellar artery - ANSWER #10 - name the artery
anterior inferior cerebellar artery - ipsilateral limb Ataxia, contralateral loss of pain and
temperature
Lateral pontine syndrome (fACIAl): loss of taste, lacrimation, salivation, hyperaucusis
ipsilateral; ipsilateral paralysis of face - ANSWER #14 - name the artery. Name the
stroke symptoms associated with occlusion of this artery.
posterior inferior cerebellar artery - lateral medullary / Wallenberg syndrome
PIC - Pain and temperature, Ipsilateral loss on face, Contralateral loss on body. Horner
syndrome (small pupil, ptosis, decreased sweating; "pH = PICA/Horner"). - ANSWER
,#16 - name the artery. Name the stroke symptoms associated with occlusion of this
artery.
vertebral artery - ANSWER Name this artery.
posterior limb of the internal capsule - ANSWER A lacunar stroke of what area would
cause a pure motor stroke, or lower extremity ataxia?
ventroposterolateral nucleus of thalamus - ANSWER A lacunar stroke of what area
would cause a pure sensory stroke?
basilar pons - ANSWER A lacunar stroke of what area would cause dysarthria/clumsy
hand syndrome?
Mechanism of action: NRT binding induces Na influx or Cl influx
Outcome effect: excitation or inhibition of membrane
Receptor / NRT: nicotinic AChR (ACh), NMDA (glutamate), 5HT-3 (serotonin), GABA-A
(GABA)
# transmembrane receptors: 4 transmembrane receptors on each of 5 subunits within
one receptor - ANSWER For the ionotropic receptor subtype, give the mechanism of
action, outcome effect, example receptor/ neurotransmitter pairs within this subtype,
and the number of transmembrane receptor units.
Mechanism of action: NRT binding induces physical transformation of receptor, G
protein activation, adenylyl cyclase enzyme activation, formation of second messenger
(cAMP or IP3), activation of protein kinase, phosphorylation of transcription factor
Outcome effect: gene transcription
Receptor / NRT: muscarinic AChR (ACh), alpha, beta (NE, E), mu (endorphins,
enkaphalins), 5HT other than 3 (serotonin), D1, D2 (DA)
# transmembrane receptors: 7 - ANSWER For the G-protein coupled receptor subtype,
give the mechanism of action, outcome effect, example receptor/ neurotransmitter pairs
within this subtype, and the number of transmembrane receptor units.
Mechanism of action: dimerization of 2 monomer subunits, phosphorylation of tyrosine,
enzyme activation, gene transcription
Outcome effect: neurogenesis
Receptor / NRT: VEGF, FGFR (BDNR, other neurotrophic factors) - ANSWER For the
receptor tyrosine kinase receptor subtype, give the mechanism of action, outcome
effect, and example receptor/ neurotransmitter pairs within this subtype.
Mechanism of action: hormone diffuses across cell membrane, hormone-receptor
complex enters nucleus and binds DNA
Outcome effect: gene transcription
Receptor / NRT: thyroid hormone, estogen, progesterone, androgens (testosterone),
cortisol, aldosterone - ANSWER For the nuclear receptor subtype, give the mechanism
, of action, outcome effect, and example receptor/ neurotransmitter pairs within this
subtype.
Autoreceptors are receptors for regulation of NRT release, bound by the same NRT
which they release.
Somatodenditic receptors - presynaptic GPCR, cause opening of K channels and
decreased cAMP levels. Regulate neuron firing rate, ex inhibitory 5HT-1A.
Nerve terminal receptors - postsynaptic GPCR, cause closing of Ca channels. Ex alpha-
2 inhibit NE release (MOA of clonidine) - ANSWER Define autoreceptors. Describe the
two types of autoreceptors and provide an example of each.
alpha-2 agonist; agonism of this nerve terminal receptor inhibits NE release. Tx for
ADHD, nightmares in PTSD - ANSWER Give the mechanism of action of clonidine and
the clinical use.
Heteroreceptors are receptors for regulation of NRT release, but they are bound by a
NRT other than the one they regulate.
5HT (serotonin) binds DA presynaptic neuron and decreases DA release d/t decreased
firing rate.
NE binds alpha-1 receptors on 5HT neurons and increase the firing rate. - ANSWER
Define heteroreceptors and give two examples.
desensitization - chronic activation of a receptor causes it to be overphosphorylated and
signaling cascade is blocked
down-regulation - chronic desensitization causes degradation of receptor
SSRIs chronically activate 5HT-1A autoreceptors, which down-regulate and result in
less inhibition of 5HT action - ANSWER Describe receptor desensitization and down-
regulation. Give an example.
Chronic antagonism of a receptor causes increased receptor synthesis, resulting in
increased NRT sensitivity.
Ex: chronic antipsychotic use (D2 blockade) increases sensitivity to DA and causes
tardive dyskinesia - ANSWER Describe the mechanism of receptor upregulation. Give
an example.
1) allosterically bind and inhibit the 5HT reuptake transporter so more 5HT is available
in the synapse
2) chronically activate 5HT-1A autoreceptors, which down-regulate and result in less
inhibition of 5HT action - ANSWER Give two main mechanisms of action for SSRIs.
tryptophan -tryptophan hydroxylase-> 5HTP -decarboxylase->5HT
dorsal raphe nucleus in the pons and medulla - ANSWER Give the synthesis pathway
for 5HT (serotonin). Give the primary location of 5HT synthesis.
VMAT - ANSWER Name the enzyme which packages monoamine neurotransmitters
(e.g. 5HT, DA, NE) into vesicles