Exam 3 Flashcards
that question:
recording current induced by NMDA in a cell that only has NMDAR as a glutamate receptor. (A) has the cell at 0 mV and (B) has the cell at -65 mV. what happens?
neither has a current; 0mV is reversal potential and -65mV is where Mg blocks the NMDA receptor.
How many glia are there (comparative to neurons)
about even
what do satellite cells do
astrocytes but in PNS, metabolic and structural supoort
what do ependymal cells do
epithelial linking of ventricles, produce CSF
difference in myelination of oligodendrocytes and schwann cells
1 oligo = many axon sections (up to 50)
1 schwann = one axon section
where are oligodendrocytes from in development
neural tube
where are schwann cells from in development
neural crest
what does myelin do
increase rate of passive depolarization –> speed up action potential
what is the major dense line
cytoplasmic surface; the area that was the inner part of the membrane that once had cytoplasm
what is the minor dense line
extracellular surface; the area that was the outer part of the membrane, the part that faced the exterior
what is the intraperiod line
extracellular space between trow minor dense lines
what is the myelin sheath made up of
mostly lipid, little protein
what are the major proteins in myelin
Myelin Basic Protein (MBP) Proteolipid Protein (PLP) Protein zero (P0)
what protein is only in PNS?
P0
what disease is associated with defective P0?
Dejerine-Sottas
what disease is associated with defective PMP22?
charcot-marie-tooth 1
what disease is associated with defective connexin 32?
x-linked charcot-marie-tooth
what disease is associated with defective MBP?
shiverer mouse; tremors and eventually seizures
myelin is abnormal in CNS but not in PNS
what is Guillain Barre Syndrome
autoimmune demyelination of PNS
triggered by infection
better prognosis than MS
what is MS
autoimmune demyelination of CNS
triggered by environmental factors
poor prognosis
what is the most abundant glial type
astrocytes
what is the filament protein in astrocytes
GFAP
what do astrocytes do
homeostasis
neurotransmission
development and plasticity
response to injury
what do astrocytes do for homeostasis
energy storage in glycogen
neuronal survival
maintain BBB
what do astrocytes do for neurotransmission
reuptake neurotransmitters
release enzymes that degrade/ inactivate NTs
gliotransmission –> release glutamate in wave form
what do astrocytes do or development and plasticity
guidance of migrating neurons (radial glia that later form neurons in development)
synapse formation and plasticity neurotransmitters
what do astrocytes do for injury
produce glial scars
“astrogliosis”
what is a tripartite synapse
a synapse with a pre synaptic, post synaptic, and astrocyte endfeet
astrocytes will soak up extra NT
how do astrocytes affect the BBB
they surround the blood vessels to prevent molecules from leaking through
what NT can astrocytes take up
glutamate, GABA
where do astrocytes take up K+?
at synapse and nodes of Ranvier
name the 4 atypical neurotransmitter
glutamate
ATP
adenosine
serine
what activates astrocytes to release NTs?
voltage gated Ca2+
why are astrocytes important in fMRI
they connect neurons to the blood vessels and control the changes in blood oxygen levels, remember fMRI is an indirect measure of activity
what is the PNS version of astrocytes
satellite cells derived from neural crest
where are microglia develop from
embryonic yolk sac
how do microglia affect development
pruning of synapses and dendritic spines
which glia have cilia and what do they do
ependymal cells, they move the CSF
what overarching type of glia is a radial glia cell
astrocyte
which NT group is also called small molecule NTs
Classical
which NTs are synthesized at the synaptic terminals
classical
which NTs are synthesized at the soma
neuroactive peptides
which NTs are in round vesicles
classical
which NTs are in large vesicles? what are the vesicles called?
neuroactive peptides. dense core vesicles
which NTs are exocytosed through CA2+ channels at active zones
classical
which NTs are exocytosed like glands
neuroactive peptides
which NTts are released by a single action potential
classical
which NTs are released by multiple action potentials
neuroactive peptides
which NTs can be released by the soma and dendrites
neuroactive peptides
which NTs can be reuptaked
classcial
what is different about Ach reuptake
it is degraded from NE to E then reuptaked
which NTs are ONLY classical
the amino acids; glutamate, GABA, glycine
name the 3 aa NTs
GABA, Glutamate, glycine
name the 5 biogenic amine NTs
dopamine, NE, E, 5-HT, histamine
which 3 NTs are the catecholamines? what is a catecholamine?
dopamine, NE, and E. They are all derived from tyrosine
can make dopamine into NE and NE into E
which enzyme produces ACh
choline acetyltransferase
what enzyme deactivates ACh and what does it turn it into
ACh esterase and it turns into choline
what gets taken up after ACh is degraded and by what
choline by choline transporter
what funct is ACh important for
autonomic and somatic motor neurons
what areas have cholinergic neurons
the entire forebrain
what is serotonin derived from
tryptophan
what does tyrosine hydroxlyase do?
turn tyr into dompamine
what does dopamine beta hydroxylase do
catalyses DA to NE
only in NE-ergic neurons not DA-ergic
what is an autoreceptor
a receptor on a presynaptic cell that senses NTs released by itself; important for modulating release
which NTs have autoreceptors
DA, NE
what does VMAT do
transports monoamines into vesicles
