3/22 neuro Flashcards
Short acting benzos?
-mnemonic?
TOM acts fast
- triazolam
- oxazepam
- midazolam
*also alprazolam. AL bundy has a short fuse.
Essential tremor
-Tx:
propanolol
-2nd line = primidone.
3 major types of glial cells
astrocytes, oligodendrocytes, microglia
astrocytes & oligodendros
-derived from what tissue?
neuroectoderm
which hypoT nucleus maintains circadian rhythm?
-mnemonic?
suprachiasmatic nucleus
-hard to be “super charismatic” when you have jet lag.
All sensory information goes through thalamus except:
olfaction
When a pt needs IV ABxs, can oral ABxs be a good enough substitute?
no
-oral ABxs do not adequately penetrate the CSF.
heroin withdrawal
-key Sxs:
dilated pupils
yawning
lacrimation
Alcohol & benzo withdrawal
-key Sxs:
tachy
seizures
nicotine withdrawal
-key Sxs:
inc. appetite
Seizures
-opioid or alcohol withdrawal?
alcohol withdrawal can produce seizures, opioid withdrawal does NOT.
*benzo withdrawal can also lead to seizures.
nicotinic receptor
-how many ACh need to bind for channel to open?
2
chlorpromazine
-high or low potency?
low potency antipsychotic
fluphenazine
-high or low potency?
high potency antipsychotic
entacapone
-mech?
peripheral COMT inhibitors, prevent L-DOPA degradation, increased dopamine availability.
entacapone vs tolcapone
-difference?
Entacapone inhibits peripheral COMT while tolcapone inhibits both central & peripheral COMT.
MAO-B
-degrades what?
dopamine
MAO-A
-degrades what?
NE & serotonin
Which receptor causes mydriasis?
alpha1
What nerve inn. all the muscles of mastication?
V3 (mandibular) of the trigeminal
which muscle opens the jaw?
lateral pterygoid
Mandibular n. (V3, trigeminal)
-exits skull through which foramen?
foramen ovale
Maxillary n. (V2, trigeminal)
-exits skull through which foramen?
foramen rotundum
TCAs
-blockade of what leads to arrythmias?
cardiac fast sodium channels
*also keep in mind, blockade of muscarinic receptors can also cause tachy.
TCAs have inhibitory effects on what receptors?
- NE & serotonin reuptake
- muscarinic
- alpha-1
- histamine
- cardiac fast Na channels
Whats the most common cause of death in pts w/anti-depressant toxicity?
TCAs inhibit cardiac fast sodium channels resulting in arrythmias.
ant pit
-derived from what tissue?
rathke pouch = surface ectoderm
post pit.
-derived from what tissue?
neural tube (which is from ectoderm).
Alar plate
- ventral or dorsal?
- motor or sensory?
(dorsal): sensory
Basal plate
- ventral or dorsal?
- motor or sensory?
(ventral): motor
Brainstem
-components:
midbrain + pons + medulla = brainstem.
Forebrain
- aka?
- what does it develop into?
- AKA: prosencephalon
- telencephalon => cerebral hemispheres
- diencephalon => thalamus
Midbrain
- aka?
- what does it develop into?
- AKA: mesencephalon
- midbrain
Hindbrain
- aka?
- what does it develop into?
- AKA: rhombencephalon
- Metencephalon => pons + cerebellum
- Myelencephalon => medulla
3rd ventricle
-which part of brain?
thalamus
aqueduct of sylvius
-which part of brain?
midbrain
Neural crest
-origin of what nervous system structures?
PNS neurons, Schwann cells.
whats the resident macrophage of the CNS and what layer does it derive from?
microglia
-from mesoderm like macrophages.
Order of closing of neural tube:
-rostal, middle, caudal: order?
-neural tube first closes in the middle. Then the rostal
end, then the caudal end.
Neuropores
-fuse during which week?
4th week
Failure of neuropores to close
-persistent connection btwn what two areas?
amniotic cavity & spinal canal.
Whats the marker for neural tube defect?
- and where can you measure it?
- whats a confirmatory test?
inc. AFP
- amniotic fluid & maternal serum
- inc. AChE in amniotic fluid = confirmatory test.
Spina bifida occulta
-is dura intact?
yes
-only spina bifida lesion w/intact dura.
Anencephaly
- what part of brain is missing?
- associated w/what maternal problem?
- No forebrain.
- maternal DM 1.
Holoprosencephaly
- what is it?
- which signaling pathway is fucked up?
- Failure of left and right hemispheres to separate, usually occurs during weeks 5-6.
- sonic hedgehog
Holoprosencephaly
- presentation?
- associated w/what genetic disease?
- Moderate form has cleft lip/palate, most severe form results in cyclopia.
- patau (trisomy 13)
Chiari II (Arnold-Chiari malformation)
- what is it?
- whats it cause?
- Significant herniation of cerebellar tonsils and vermis through foramen magnum
- Aqueductal stenosis and hydrocephalus
Chiari II (Arnold-Chiari malformation) -how does it present?
-Often presents with lumbosacral myelomeningocele and paralysis below the defect.
Dandy-Walker
- what is it?
- associated w/what comorbidities?
- Agenesis of cerebellar vermis with cystic enlargement of 4th ventricle.
- Associated with hydrocephalus and spina bifida.
Syringomyelia
- what is it?
- what cells are usually damaged first?
-Cystic cavity (syrinx) within the spinal cord.
-Crossing anterior spinal commissural fibers are typically
damaged first.
Syringomyelia
- Sxs:
- most common location?
- Results in a “cape-like” bilateral loss of pain and temperature sensation in upper extremities (fine touch sensation is preserved).
- Most common at C8–T1.
Ant. 2/3 of tongue
-which branchial arches?
-1st and 2nd branchial arches.
Post. 1/3 of tongue
-which branchial arches?
-3rd and 4th branchial arches
Post. 1/3 of tongue
- somatosensation via?
- taste via?
-CN 9 for both.
Which CNs carry taste sensation?
-what nucleus do they deliver this to?
CN VII, IX, X
-solitary nucleus
Ant. 2/3 of tongue
- somatosensation via?
- taste via?
- sensation = V3
- taste = CN 7
Astrocyte
-handles metabolism of what?
potassium
HIV-infected microglia: appearance?
-fuse to form multinucleated giant cells in the CNS.
Oligodendrocyte
-how many axons can it myelinate?
A lot (~30)
Oligodendrocyte
- how many axons can it myelinate?
- injured in which diseases?
- ~30.
- Injured in multiple sclerosis, progressive multifocal leukoencephalopathy (PML), and leukodystrophies.
Schwann cells
- how many axons can it myelinate?
- mnemonic?
- can only myelinate 1 PNS axon.
- Schwann bike only fits one person.
Schwann cells
- derived from?
- destroyed in what disease(s)?
- neural crest
- Destroyed in Guillain-Barré syndrome.
Most common sign of initial periph. neuropathy in DM
pts is loss of what?
-caused by damage to what?
Loss of vibration sense
-pacinian corpuscles
4 cell types in epidermis:
-langerhan dendritic cells, keratinocytes, melanocytes, merkel cells.
Endoneurium
- surrounds what?
- inflammatory infiltrate here signals what disease?
- single nerve fiber
- inflammatory infiltrate in Guillain-Barré syndrome.
Perineurium
-surrounds what?
- surrounds a fascicle of nerve fibers.
- Must be rejoined in microsurgery for limb reattachment.
Epineurium
-surrounds what?
-dense connective tissue that surrounds entire nerve (fascicles and blood vessels).
Dopamine
-location of synthesis
- Ventral tegmentum and SNc (midbrain)
* SNc = substantia nigra pars compact
Serotonin
- inc or dec in anxiety?
- inc or dec. in parkinsons?
- dec. in anxiety
- inc. in parkinsons
Serotonin
-where is it made?
Raphe nucleus (pons, medulla, midbrain)
ACh
-where is it made?
Basal nucleus of Meynert
ACh
- inc or dec in parkinsons
- inc or dec in Alzheimers
- inc or dec in Huntingtons
- inc. in Parkinson disease
- dec. in Alzheimer disease
- dec. in Huntington disease
GABA
-inc or dec. in anxiety?
-dec. in anxiety
GABA
-where is it made?
- Nucleus accumbens
* strong association w/addiction.
Tight junctions aka:
-zonula occludens.
vasogenic edema
-what is it?
-cerebral edema due to infarction and/or neoplasm destroying endothelial cell tight junctions of the BBB.
Areas of hypoT not protected by BBB:
- OVLT (organum vasculosum of the lamina terminalis) senses change in osmolarity.
- area postrema (responds to emetics)
Supraoptic nucleus makes:
ADH.
Paraventricular nucleus makes:
oxytocin.
HypoT: lateral area
- function?
- mnemonic?
- inhibited by what?
- “Lat makes you Fat”
- controls hunger
- destruction => anorexia
- inhibited by leptin
HypoT: Ventromedial area
- function?
- mnemonic?
- stimulated by what?
- If you zap your ventromedial area, you grow ventrally & medially.
- satiety center
- destruction => hyperphagia
- stimulated by leptin.
Anterior hypothalamus
- function?
- mnemonic?
- stimulated by what?
- cooling
- A/C = anterior cooling.
- parasympatheticaly stimulated.
Posterior hypothalamus
- function?
- stimulated by what?
- heating
- sympathetically stimulated
Suprachiasmatic nucleus
- function?
- mnemonic
- Circadian rhythm.
- “Hard to be “super charismatic” when you have jet lag”.
Suprachiasmatic nucleus
- how does it stimulate pineal gland?
- what does pineal gland release when stimulated?
-Suprachiasmatic nucleus squirts NE onto pineal gland which then releases melatonin.
Two stages of sleep:
-rapid-eye movement (REM) and non-REM.
Extraocular movements during REM sleep due to activity of:
-PPRF (paramedian pontine reticular formation/conjugate gaze center).
How often does REM sleep occur?
Every 90 minutes, and duration increases through the night.
What decreases REM & delta wave sleep?
-Alcohol, benzodiazepines, barbiturates, & norepinephrine.
Bedwetting: Tx:
Oral desmopressin acetate (DDAVP).
-preferred over imipramine.
Night terrors and sleepwalking: Tx:
Benzodiazepines
What stage of sleep does sleepwalking, night terrors, and
bedwetting occur?
Non-REM: stage N3
-delta wave sleep
What stage of sleep does bruxism occur?
Non-REM: stage N2
-Sleep spindles and K complexes
Thalamus: VPL nucleus
-inputs?
Spinothalamic & DC/ML
Thalamus: VPM nucleus
- inputs?
- mnemonic?
- inputs: trigeminal and gustatory pathway
- “M”akeup goes on the face (vp”M”)
Thalamus: LGN nucleus
- inputs?
- destination?
- mnemonic?
- input: CN2
- Calcarine sulcus (visual cortex)
- Lateral = Light
Thalamus: MGN nucleus
- inputs?
- destination?
- mnemonic?
- input: Superior olive and inferior colliculus of tectum.
- Auditory cortex of temporal lobe.
- “M”edial = “M”usic
Thalamus: VL nucleus
- inputs?
- destination?
- inputs: Basal ganglia, cerebellum.
- Motor cortex
Limbic system
-involves which sense?
olfaction
Cerebellum
-output nerves?
Purkinje cells
-the only output cells of the cerebellum.
Which cells in cerebellum are very vulnerable to ischemia?
Purkinje cells
Striatum =
= putamen (motor) + caudate (cognitive).
Lentiform =
= putamen + globus pallidus.
Is amygdala part of basal ganglia?
No, its part of limbic system.
Sertraline
-what is it?
SSRI
precentral gyrus
primary motor cortex
Which vitamin inc. peripheral metabolism of levodopa?
B6
Cimetidine
-s/e:
- p450 inhibitor
- anti-androgenic effects
- gynecomastia
- prolactin release
- impotence
- dec. libido
- dec. renal excretion of creatinine
What type of drugs are usually more addictive, shorter or longer acting?
shorter acting
