Cells of the CNS Flashcards
immune cells in the CNS are called?
microglia
where are ependymal cells found?
line central canal of spinal cord
low columnar/cuboidal cells
purpose of ependymal cells?
aid CSF flow via cilia
4 big characteristics of Neurons:
Specialized for signalling
high level of protein synthesis
metabolically limited
terminally differentiated
3 components of cytoskeleton and their function:
Actin: dynamic/movement
Intermediate: permanent
Microtubules: dynamic, axon transport
what is the metabolic centre of the neuron called?
soma
two types of processes that come from neuron?
dendrites: receive
axons: conducting
High proportion of total neuron volume are? 2 things
Axons
dentrites
why is axonal transport critical?
because so much of the neuron is axon
nerve damage is usually where on the neuron?
axon because it’s so long
Neuron input via dendrites is active or passive?
passive electrotonic spread
why do neurons have high protein production?
to make ion channels
receptors
cytoskeleton
What are Nissl bodies?
rough ER and ribosomes in neurons
Glial cells AKA:
macroglia
Astrocytes have 5 key passive support functions:
NT uptake/degradation K+ homeostasis neuronal energy supply BBB maintenance injury response/recovery
2 active functions of astrocytes:
modulate neuronal function module neuronal blood flow
Glutamate does what?
excite
GABA does what?
inhibit
what happens when glutamate transporters on glial cells are inhibited
neurons are more depolarized, could die
What can excite a glia? 4 things
NTs: ATP/glutamate
Trauma
Spontaneous
inflammatory mediators
how can you prove glia is active?
modulation in intracellular calcium waves
How to glia communicate?
via synaptic vesicles and exocytosis
how does glia regulate neuron?
glia release ATP>calcium wave>inhibit neurons
Which glial cells surround blood vessels? what do they do?
astrocytes:
vasoconstriction/dilation
difference between oligodendrocytes and schwann cells?
oligodendrocytes: CNS white matter
schwann: PNS
How many axons do oligodendrocytes vs. schwann cells?
oligodendrocytes: several axons
schwann: single axon
Where does microglia originate from?
bone marrow/macrophage lineage
microglia fast or slow?
fast: like innate system
microglia important for maintaining what?
normal brain function
what do microglia do if injury?
release cytokines (damaging) change rapidly in response to inflammation
peripheral nerve have 3 layers
endoneurium: around individual nerve fibre
Perineurium:around fascicles
epineurium: around entire nerve
aggregations of cell bodies of neurons outside the CNS are called?
ganglia
what do autonomic ganglia house?
cell body of post-ganglionic neurons
