Week 1 Flashcards
1
Q
How does Na/K ATPase maintain resting membrane potential?
A
N/K ATPase - uses ATP and counteracts the movement of Na and K. Does this by moving 3 Na ions out of cell for every 2 K+ ions into cell)
@resting potential
*Na is more concn outside the cell (extracellular) but moves inward due to concn gradient - so Na/K ATPase acts to keep Na more concn outside the cell
*K is more concn inside the cell (intracellular) but moves outward due to concn gradient - so Na/K ATPase acts to keep K more concn inside the cell
2
Q
What happens to potential when Na/K ATPase is inhibited?
A
You would see an immediate change in the membrane potential because you remove a hyperpolarizing current (remember resting potential is about -65), in other words, the membrane potential becomes less negative.
3
Q
Describe the activity of the Na and K voltage gated channels during resting state
A
- Na - activation gates closed/inactivation gates open
- K - activation gates closed
4
Q
Describe the activity of the Na and K voltage gated channels when threshold is reached
A
- Na- activation gates partially open/inactivation gates open (minor Na influx into cell)
- K - activation gates closed
5
Q
Describe the activity of the Na and K voltage gated channels during rising phase of AP
A
- Na - activation gates fully open/inactivation gates open (but inactivation gates begin to close during overshoot) -> Major Na influx
- K- Activation gates partially open (minor K efflux at overshoot)
6
Q
Describe the activity of the Na and K voltage gated channels during falling phase of AP
A
- Na- activation gates open/inactivation gates closed (Na no longer moves through)
- K - activation gates fully open (major K efflux)
7
Q
Describe the activity of the Na and K voltage gated channels during undershoot phase
A
- Na - both activation and inactivation gates are closed
- K - activation gates still open but some are starting to close which causes reduced K+ efflux
8
Q
What are the three types of neurotransmitters?
A
- amino acids
- monoamines
- neuropeptides
9
Q
What neurotransmitters (2) are considered small molecule neurotransmitters?
A
amino acids and monoamines
10
Q
What are the three amino acid neurotransmitters?
A
- glutamate (excitatory)
- GABA (inhibitory)
- Glycine
11
Q
What are the three monoamine neurotransmitters that derive from tyrosine?
A
- serotonin (5-HT)
- Dopamine (DA)
- Norepinephrine (NE)
12
Q
What are the 5 monoamine neurotransmitters? (3 of them are derived from tyrosine)
A
- 5-HT
- Dopamine
- NE
- Epi
- Histamine
13
Q
(Neuropeptides vs Small molecule NTs) -> which of the two are made in the soma and packaged into synaptic vesicles which are then transported down to axon terminal via microtubules?
A
Neuropeptides
14
Q
(Neuropeptides vs Small molecule NTs) -> Which of the two are made like this:
* NT precursors are transported into axon terminal first
* Then made into actual NT packaged into synaptic vesicles
A
small molecule NTs
15
Q
Differentiate ionotropic vs metabotropic receptors
A
- Ionotropic - a large protein with extracellular domain that binds ligand and a transmembrane domain that allows for ion transport. -> has rapid and transient responses in membrane potential
- Metabotropic - G protein coupled receptors that can have a variety of functions (gating of ions or activating 2ndary messenger pathway)
16
Q
What is temporal summation
A
Rapid PSPs (postsynaptic potentials) from the same source/pre-synaptic neuron -> when added together they may be inhibitory or excitatory
17
Q
What is spatial summation
A
PSPs from different sources arrive almost or at the same time at the same neuron -> when added together they may be inhibitory or excitatory
18
Q
soma indicates association with what body parts?
A
skin, muscle, bone
19
Q
Schwann cells vs Oligodendrocytes
1. which are found in the CNS vs PNS
A
- Schwann are in the PNS
- Oligodendrocytes are in the CNS
20
Q
Parasympathetic vs Sympathetic - which one has ganglia in the PNS and far from their terminal target viscera?
A
- sympathetic
- parasympathetic NS has ganglia in or very near their target viscera
21
Q
What three structures make up the brainstem?
A
- Midbrain
- Pons
- Medulla
22
Q
Lenticular nucleus in the cerebral hemispheres are made up of what two structures?
A
putamen and globus pallidus
23
Q
Gray matter vs white matter - which one is the cell body and which one is the axons
A
Gray matter is the neuronal cell body and white matter is axons (nerve fibers)
24
Q
What gyrus has the primary motor cortex and which one has primary somatosensory cortex (they are close)
A
- PRECENTRAL - Primary motor cortex
- POSTCENTRAL - Primary somatosensory cortex
25
What brain system is involved in our behavioral and emotional responses, especially those for survival like feeding, reproduction, and caring for young
Limbic system
27
What core structures are involved in the limbic system? (3)
1. Hypothalamus
2. Amygdala
3. Hippocampus
28
What major artery supplies anterior circulation of the brain and eventually gives way to branches including the middle and anterior cerebral artery?
Internal carotid arteries
29
What artery supplies blood to back of brain (near cerebellum)?
Vertebral arteries
30
What arteries supply blood to the back of the cerebral part of the brain?
Posterior cerebral artery
31
What does the middle cerebral artery supply?
The lateral portions of the cerebrum
32
The ventricular system is found between what two layers of meninges?
1. between the arachnoid and pia mater
33
What structure of the brain is the third ventricle found within?
Diencephalon
34
What structure of the brain is the cerebral aqueduct found within?
midbrain
35
What structure of the brain is the fourth ventricle found within?
hindbrain (pons, medulla, cerebellum)
36
Explain what the (primary vesicles in embryos)
1. prosencephalon
2. Mesencephalon
3. Rhombencephalon
become in the brain for a fully developed human
1. forebrain (hemispheres, thalamus, hypothalamus)
2. midbrain (cerebral peduncles, midbrain tectum, midbrain tegmentum)
3. hindbrain (pons, cerebellum, medulla)
37
Explain what the (2ndary vesicles in embryos)
1. Telencephalon
2. Diencephalon
3. Mesencephalon
4. Metencephalon
5. Myelencephalon
become in the brain for a fully developed human
1. cerebral hemispheres
2. thalamus, hypothalamus
3. cerebral peduncles, midbrain tectum, midbrain tegmentum
4. pons, cerebellum
5. medulla
38
What nuclei that contains preganglionic parasympathetic neurons that facilitate pupillary construction in response to light
Edinger-Westphal
39
Location of cell bodies of sympathetic preganglionic neurons
lateral horn (intermediolateral nuclei) of the spinal cord
40
Neurotransmitter released by most postganlionic sympathetic nerves
Norepinephrine
41
The nerves for the sympathetic nervous system arise from what levels of the spinal cord?
T1-L3
42
The major effector NT for sympathetic nervous system is (Blank A) and receptor is (Blank B)
Blank A - Norepinephrine
Blank B - Adrenergic Receptor (Alpha1, alpha2, beta1, beta2, beta3)
43
The major effector NT for parasympathetic nervous system is (Blank A) and receptor is (Blank B)
Blank A - Acetylcholine
Blank B - muscarinic receptor
44
1. SNS activity on the adrenal glands is via what NT and what receptor ?
2. This leads to what?
1. Acetylcholine on nicotinic receptor
2. release of hormones from adrenal medulla
45
1. SNS activity on the sweat glands is via what NT and what receptor ?
2. What does this cause
1. Acetylcholine on M3 receptor
2. Leads to sweating
46
1. SNS activity on the renal vasculature is via what NT and what receptor ?
2. What does this lead to?
1. Dopamine on the D1 receptors
2. leads to vasodilation of blood vessels at low dosages
47
Alpha 1
1. SNS or PNS?
2. What NT acts on it?
3. Activation of this causes what?
1. SNS
2. norepinephrine
3. found on vascular smooth muscle -> NE leads to vasoconstriction to raise BP
48
Beta 2
1. SNS or PNS?
2. What NT acts on it?
3. Activaiton of this causes what? (2)
1. SNS
2. Norepinephrine
3. Found on muscle and liver blood vessels -> to cause vasodilation + Found on bronchioles smooth muscle -> causes bronchodilation
49
M2 receptor (muscarinic)
1. SNS or PNS?
2. What NT acts on it?
3. Causes what?
1. PNS
2. ACh
3. found on the heart -> activation of this causes slow heart rate
50
M3 (muscarinic)
1. SNS or PNS?
2. What NT acts on it?
3. Causes what?
1. PNS
2. ACh
3. PNS activty in a lot of locations including blood vessels (vasodilation), lungs (bronchoconstriction), and salivary glands (watery saliva)
51
How does ACh (PNS) cause smooth muscle relaxation?
Acetylcholine indirectly leads to smooth muscle relaxation. ACh triggers release of NO (endothelium derived relaxing factor) and causes muscle relaxation
52
What NT and receptors are used in GANGLIA of both SNS and PNS
NT - ACh
Nicotinic receptors
53
SNS activity on heart -> activates what receptor to increase heart rate?
Beta 1 receptor (adrenergic receptor)
54
Skin is under SNS control
1. What receptor is activated to cause vasoconstriction of blood flow through skin?
1. alpha 1 receptors (adrenergic)
55
PNS activity on heart -> activates what receptor to decrease heart rate?
M2 receptor (cholinergic)
56
SNS activity on pupils -> activates what receptor to dilate pupils?
alpha 1 (adrenergic)
57
PNS activity on pupils -> activates what receptor to constrict pupils?
M3 (cholinergic)
58
Accomodation of eyes (constriction for near vision) is mostly under SNS or PNS control?
PNS (via M3 receptor)
59
Major neurotransmitter of somatic neurons is (blank A) and they work on (blank B) receptor
Blank A - acetylcholine
Blank B - Nicotinic
60
What are the SNS and PNS effects on sweat glands?
1. SNS - secretion
2. PNS -none
61
What is the effect of the SNS and PNS system on the bladder detrusor muscle?
1. SNS - relaxation
2. PNS - constriction
62
Things that are more dense appear (white or black) on a CT scan?
Appear white/lighter
| Includes bone, hemorrhage (high protein), metal, calcificaiton, Iodine
63
T2 MRI Sequence
1. higher signal for more (Blank A)
2. low signal for (Blank B)
1. water
2. fat
64
What is (DWI) Diffusion Weighted Imaging MR sequence imaging used for?
1. Measures restricted water diffusion -> highly sensitive to Acute ischemic stroke or abscess
* Acute stroke is first worked up with non-contrast CT then this MRI to identify if it is acute ischemia and not hemorrhagic
65
In CT what appears dark, gray or white matter?
white matter
66
What head injuries is CT w/out contrast able to detect?
1. head trauama, skull fracture
2. hemorrhages
3. hydrocephalus
4. Intracranial masses
5. Stroke
6. Calcification
67
What head injuries is CT with contrast able to detect?
1. intracranial tumors
2. infection
3. Eval of intracranial vasculature
| Don't use if allergy to iodine or severe renal insufficiency
68
Epidural Hematoma
1. Where is the hemorrhage found
2. Injury to what artery or vein
3. shape of lesion on CT scan
1. between dura and skull
2. Middle meningeal
3. biconvex
69
Subdural Hematoma
1. Where is the hemorrhage found
2. Injury to what artery or vein
3. shape of lesion on CT scan
1. between dura and arachnoid
2. Damage to bridging veins
3. crescent shape
70
Subarachnoid Hematoma
1. What causes this most often?
2. common symptom?
3. Typical CT scans show
1. ruptured berry aneurysm
2. thunderclap headache + photophobia, nuchal rigidity
3. in images
71
What are Nissl Bodies
Dark staining ER/Ribosomes in the neuron cell body -> soma makes tons of proteins
72
What types of cells are these?
CNS Glial cell- astrocytes
73
Astrocytes
1. Function
2. Stain positive for
3. Shape of cells in histology
1. structural support, scavenge NT and ions in synapse, form neural scar
2. GFAP
3. large star shaped cells
74
What type of junctions are in the blood brain barrier
tight junctions
75
Oligodendrocytes vs Schwann Cells
1. Which myelinates multiple axons at the same time
1. oligodendrocytes
76
What cell type is this?
CNS Glial cell - Microglia
* Small, cigar shaped nuclei
77
What is the purpose of microglia cells?
1. Immune defense for CNS
2. Initiate inflammatory response
3. Phagocytose cell debris after injury
4. Glial scar formation
78
What type of cells make up the choroid plexus of the ventricles of the brain?
1. specialized ependymal cells. These produce CSF from blood.
79
What kind of cells are these?
PNS Glial cells - Satellite cells
80
Function of satellite cells?
1. Insulate neurons from electrical impulses
2. Metabolic support
81
Which is endoneurium, epineurium, and perineurium?
1. Blue arrow - epineurium (connective tissue covering that contains blood vessels, adipose, and the axons)
2. Yellow arrowhead - perineurium (wraps a bundle of axons)
3. Gree triangle - endoneurium (surrounds individual axons)
82
What is Wallerian degeneration of an axon?
Axon segment distal to injury degrades when there is axonal injury
83
Which has better axon regeneration skills and why? (CNS vs PNS)
1. PNS
2. CNS has blocks to regeneration -> macrophages can't enter to clear debris, glial scar forms instead and growth cone can't reach target
84
Granule cells have what function in cerebral cortex?
Interneurons (round cell bodies)
85
What is neuropil?
Dense weaving of neuronal and glial processing (usually background of histology images)
86
What glial cell has a halo around the cell?
Oligodendrocytes
87
What are the remaining layers of the cerebral cortex
1. Plexiform layer (red) - mostly nerve fibers
2. (Blank 1)
3. Medium pyramidal cell layer (green) - pyramidal cells slightly larger
4. (Blank 2)
5. Large pyramidal cell (ganglionic) layer (dark blue) - landmark layer
6. (Blank 3)
1. Plexiform layer (red) - mostly nerve fibers
2. Small pyramidal cell layer (yellow) - small pyramidal cells and granule cells
3. Medium pyramidal cell layer (green) - pyramidal cells slightly larger
4. Granular layer (blue) - higher # of granule cells, few pyramidal cells
5. Large pyramidal cell (ganglionic) layer (dark blue) - landmark layer
6. Polymorphic cell layer (dash) - variable cell shapes and types
7. Brown- white matter
88
What are the remaining layers of the cerebral cortex
1. (Blank A)
2. Small pyramidal cell layer (yellow) - small pyramidal cells and granule cells
3. (Blank B)
4. Granular layer (blue) - higher # of granule cells, few pyramidal cells
5. (Blank C)
6. Polymorphic cell layer (dash) - variable cell shapes and types
1. Plexiform layer (red) - mostly nerve fibers
2. Small pyramidal cell layer (yellow) - small pyramidal cells and granule cells
3. Medium pyramidal cell layer (green) - pyramidal cells slightly larger
4. Granular layer (blue) - higher # of granule cells, few pyramidal cells
5. Large pyramidal cell (ganglionic) layer (dark blue) - landmark layer
6. Polymorphic cell layer (dash) - variable cell shapes and types
7. Brown- white matter
89
What part of the spinal cord cross section is gray and white matter?
1. butterfly middle area is ...
2. Outer region is...
1. gray matter
2. white matter
90
Describe which is the purkinje cell layer, granular layer, and molecular layer?
1. Blue bracket - molecular layer (few cells, many projections)
2. Arrow - purkinje cell layer (large purkinje cells)
3. Brown bracket - granular layer (densely packed neurons)
91
1. What is neuropraxia?
2. What is the prognosis
1. Mild peripheral nerve damage (only myelin sheath is damaged)
2. excellent recovery
92
1. What is axonotmesis?
2. What is the prognosis?
1. (myelin and part of axon is damaged) Moderate peripheral nerve damage
2. depends on many factors but it is possible if Schwann cells maintain integrity
93
1. What is neurotmesis?
2. What is the prognosis?
1. Severe peripheral nerve damage (damage to the epineurium, perineurium, endoneurium, myelin sheath, and axon)
2. bad prognosis - no significant regeneration occurs
94
1. What is axonal reaction in axonotmesis?
2. What is another name for this?
1. This occurs proximal to axon lesion. It is also called **central chromatolysis **
2. There is up-regulation of protein synthesis for repair.
3. Cell body changes - including swelling, chromatolysis (disappearance of Nissl bodies), nucelus moves to the periphery
4. this happens all while wallerian degeneration is happening distal to the axonal lesion
95
What neurons/areas in CNS are more sensitive to ischemia? (2 main ones but 4 in total)
**1. Hippocampal cells
2. Purkinje cells**
3. Neocortex
4. Striatum
96
What occurs 12-24 hours after ischemia in the CNS (causing central nerve damage)
1. Microvacuoles (small holes) develop in neuron cytoplasm
2. Neurons become "red neurons" - necleus changes shape, color
97
What occurs 24-48 hours after ischemia in the CNS (causing central nerve damage)
1. Liquefactive necrosis occurs after neturophils, macrophages, and microglia are activated
98
What occurs days to weeks after ischemia in the CNS (causing central nerve damage)
1. Macrophages eliminate debris and a cyst forms
2. Astrocytes form a wall around cyst
99
What are rosenthal fibers and when do they appear?
1. Intracytoplasmic inclusions that occur with injury in CNS -> elongated beaded structures in astrocytic processes
2. Seen in low grade gliomas or long standing gliosis
100
What two conditions show lewy body?
1. Parkinsons
2. Lewy body dementia
101
What disease often has negri body?
1. rabies
| A intracytoplasmic inclusion
102
Astrocytes proliferate in response to pathology (gliosis) -> they can take on two different morphology types which are...
1. Fibrillary Astrocytes - star shape radial processes
2. Gemistocytes - plump pink cytoplasm and stubby processes (image)
103
What are corpora amylacea?
1. An intracytoplasmic inclusion that forms as a reactive change in astrocytes.
2. Normal increase with age
104
1. What are microglial nodules made up of?
2. When does this occur?
1. Made up of a group of reactive microglial cells (rod cells)
2. this can appear in chronic encephalitis
105
1. The vertebral arteries are a branch of what artery?
2. Where do they enter the skull
1. Branch from the subclavian artery
2. foramen magnum
106
What are the 5 branches of the internal carotid artery in the brain?
1. opthalmic artery
2. Posterior communicating artery (PCA)
3. anterior choroidal artery
4. Anterior cerebral artery
5. Middle cerebral artery
107
Why are transporters in the BBB important?
1. They are necessary to allow entry of glucose for energy
2. Glucose is absorbed via blood brain barrier to astrocyte via GLUT1 and then processed to make lactate which is transferred to neuron and neuron can then use it as energy
108
1. What gives brain the energy it needs in fasting state?
1. there are **small** glycogen storage but rapidly go to gluconeogenesis
109
1. What gives brain the energy it needs in starved state?
1. Gluconeogensis through fat and protein catabolism.
2. Blood levels of ketones rise
3. Glucose is spared and only used for a few things like NT production
110
Describe the flow of CSF starting with ventricles (~6 steps)
1. CSF is made by ependymal cells of ventricles - starting with lateral ventricles -> interventricular foramen
2. Move toward third ventricle -> Then aqueduct of midbrain
4. Fourth ventricle
5. Subarachnoid space
6. Dural sinuses (image) -> internal jugular vein
111
1. What are circumventricular organs?
1. Sites along the 3rd and 4th ventricle where BBB is ineffective or absent. This allows for communication between the blood, brain, and CSF
112
1. How does the area postrema cause vomiting?
1. This is a circumventricular organ so BBB is ineffective
2. Neurons respond rapidly to something "toxic" in blood and this triggers emesis
113
Protein composition of CSF normally
1. low protein in CSF - high protein can indicate pathology
114
What is non-communicating hydrocephalus?
1. there is an obstruction of flow within ventricles causing a buildup of CSF
115
What is communicating hydrocephalus?
1. Build up of CSF due to impaired CSF reabsorption - this is usually due to meningitis
116
What is ex vacuo hydrocephalus
1. When a stroke or injury damages the brain and brain matter shrinks so CSF volume increases to fill the extra space.
2. The ventricles are enlarged, but the pressure usually is normal.
117
GABA and Glycine are inhibitory NT
1. What areas do they each work on?
1. GABA - cortex, midbrain, and cerebellum
2. Glycine - spinal cord and much of the brainstem
118
What is the difference between GABA-A and GABA-B receptors?
1. GABA-A is ionotropic - permeable to Cl ions to make membrane potential more negative
2. GABA-B is metabotropic - coupled to Gi/o proteins for inhibitory activity (activate GIRKs or inhibit Ca channels)
119
What type of receptors are glycine receptors (ionotropic or metabotropic)?
1. ionotropic - fast inhibitory action
120
What are the types of metabotropic glutamate (excitatory) receptors?
1. Gq - activates phospholipase C (group I)
2. Gi/o (group II) - principally presynaptic and inhibit neurotransmission
3. Group II receptors - also Gi/o but that modulate other receptors
121
What are the three main types of glutamate receptors?
1. AMPA
2. Kainate - principally modulates presynaptic functions
3. NMDA- involved in memory and motor control
| all ionotropic
122
What are monosynaptic reflex (1A)?
1. This is a reflex arc that provide **direct** communication between sensory (1A afferent) and motor neurons innervating the muscle
2. Signal comes from muscle spindles
123
What is a disynaptic reflex (1B)?
- This involves an inhibitory interneuron
1. The afferent nerve is activated by excess stress on tendon -> release of glutamate to excite inhibitory interneuron
2. Inhibitory interneuron release glycine to inhibit motor neurons projecting to muscle (causes muscle to relax)
| This is for reverese myotatic reflex
124
What is axonal shearing in relation to head truama?
The shearing (tearing) of the brain's long connecting nerve fibers (axons) that happens when the brain is injured as it shifts and rotates inside the bony skull.
125
1. What is included in Cushing's Triad
2. When does this happen?
1. hypertension, bradycadia, irregular respiration
2. most commonly caused by a head injury, bleeding in the brain (i.e. hematoma or hemorrhage), tumor, infection, stroke, excess cerebrospinal fluid, or swelling of the brain.
126
Differentiate primary brain injury vs secondary brain injury?
1. primary - direct mechanism leading to brain injury like external force, rapid acceleration, penetrating injury
2. secondary - cascade of molecular injury that were initiated at point of trauma and continue for hours to days
127
Differentiate coma and unconsciousness
1. Coma - unresponsive state where patient cannot be aroused, lack sleep-wake cycle, etc
2 Unconsciousness - can either be **drowsiness** (light sleep and easy arousal), **stupor** (deeper sleep like state and unable to maintain alertness), **minimally conscious state** (awake but poorly responsive), and **vegetative state** (awake but unresponsive, eyes open, yawning, coughing, swallowing)
128
1. Trauma to dural arteries like middle meningeal artery
2. blood between dura and skull
3. lens shaped mass on CT
**What type of head injury is this?**
Epidural Hematoma
129
1. Trauma to bridging veins
2. blood between dura and arachnoid
3. crescent shaped mass on CT
**What type of head injury is this?**
Subdural Hematoma
*slow bleed*
130
1. Bleeds into space between arachnoid and pia mater - usually due to rupture berry aneurysms
2. symptom is "worst headache of my life", fever, nucchal rigidity
3. CT shows bleeding within brain tissue
**What type of head injury is this?**
Subarachnoid Hemorrhage
131
1. Trauma due to ruptured vessels, usually due to hypertension
2. CT shows bleeding into ventricles
**What type of head injury is this?**
Intraventricular or intraparenchymal hemorrhage
132
Cytotoxic Edema
1. What is it a consequence of/what event does it follow?
2. Status of BBB
3. MOA
1. Following brain injury/brain infarct - consequence of cellular injury
2. Intact BBB
3. Failure of ATP pump - leads to retention of water in cells -> edema
133
Vasogenic Edema
1. What is it a consequence of/what event does it follow?
2. Status of BBB
3. MOA
1. Injury that causes disruption of BBB
2. breakdown of BBB
3. Volume can pass the BBB and increase ICP
134
What is normal ICP
10-15 mmHg
135
Subfalcine Herniation
1. where is brain tissue moving?
2. vessels affected?
3. symptoms
1. cingulate gyrus moves to opposite side of brain underneath the falx (#3 in image)
2. Compresses ACA and drags it
3. Contralateral leg paresis
136
Uncal Herniation
1. where is brain tissue moving?
2. any vessels compressed?
3. symptoms
1. medial temporal lobe is moving down and around the tentorium (found above cerebellum) (#1 on image)
2. ipsilateral PCA is compressed -> leads to vision loss
3. Ipsilateral CN III compression (blown pupil), cerebral peduncle compression, etc
137
Tonsillar Herniation
1. where is brain tissue moving?
2. symptoms
1. Tonsil of cerebellum moves down through foramen magnum (#6 in image)
2. compression of medulla -> depresses centers for respiration and cardiac rhythm which leads to cardiorespiratory failure
138
1. How do hyperosmotic agents treat high ICP?
2. What are the two txs? + explain their MOA
Hyperosmotic agents will draw water out of tissue, relieving some pressure in the cranium
1. Mannitol - elevates blood plasma osmolality -> moves water from tissues (CSF from brain) and into interstitial fluid and plasma
2. Hypertonic saline - extracts fluid from swollen cerebral tissue due to mechanism of osmosis as well
139
What are the 4 components of total pain?
1. physical
2. psychological
3. spiritual
4. social
140
Recurrent (inferior) laryngeal nerve
1. location
2. Damage to this can cause what?
1. inferior pole of the thyroid lobes
2. hoarseness of voice
141
What is a Le Fort fracture
Fracture from right side to left side
142
What is behind pterion that is important to note clinically?
1. middle meningeal artery - if there is injury here then it can cause extradural hematoma
143
What veins are potential rought for infection to spread from scalp into the cranial cavity?
Emissary veins - connect veins of the scalp to the dural sinuses
144
what structure is this?
cingulate gyrus
*blood supplies by anterior cerebral artery*
145
What is the NT parasympathetic and sympathetic systems use PREGANGLIONIC?
acetylcholine (post ganglionic its different for each)
Acetylcholine is the neurotransmitter of the sympathetic and parasympathetic **preganglionic** neurons.
146
Subfalcine herniation
*also known as midline shift or cingulate herniation*
1. It is the most common cerebral herniation pattern
2. Caused by a mass effect with medial direction of the ipsilateral cingulate gyrus beneath the free edge of the falx cerebri due to raised intracranial pressure.
147
Central Herniation
1. subtype of downward transtentorial herniation of the brain that involves descent of the diencephalon and midbrain. It usually occurs with other types of downward herniation such as uncal herniation.
148
What CN is inside the carotid sheath?
CN X (vagus)
149
How is glutamate removed from the extracellular space after its released?
Glutamate is removed from synaptic cleft by diffusion and then removed from extracellular space via transmembrane proteins called EAATs
150
CT with or without contrast
1. which is better for detecting blood shortly after the onset of symptoms like subarachnoid hemorrhage?
1. CT without contrast
2. Contrast brightness can mask brightness of blood.
151
What happens when there is an increase in potassium extracellulary? How does this affect action potential and potentials?
1. Increase in K extracellularly alters the potential difference between the extracellular and intracellular space. The difference would be less and this would depolarize or "make more positive" the resting potential
