Glia and Neurotransmitters Flashcards
what are the types of glial cells
astrocytes, oligodendrites and microglia
what do astrocytes do (5)
structurally support the neurones provide nutrition to neurones removes excess neurotransmitters buffer K levels help form the BBB
how do astrocytes provide nutrition for neurones
as neurones cant store glycogen, astrocytes take in glucose and store it as lactate. this can then be converted to pyruvate to be transported to the neurones when glucose is low
what neurotransmitter is particularly toxic to neurones
glutamate
how do astrocytes help form the blood brain barrier
they help form the tight junctions between endothelial cells
what do oligodendrites do
myelinate the axons in the CNS to give insulation
what cells myelinate the neurones in the PNS
Schwann cells
true or false: each oligodendrite can only myelinate one axon at a time
false- they can myelinate may at one time
what do microglia do
they recognise foreign bodies and become activated into phagocytes
describe the release of neurotransmitters at synapses
depolarisation in the pre-synpatic bulb causes the influx of calcium ions.
Ca ions causes the vesicles containing the neurotransmitter to fuse with the pre-synpatic membrane to be released into the synaptic cleft.
the neurotransmitter then binds to receptors on the post-synaptic membrane to cause either activation/inhibition.
true or false; glutamate is excitatory
true
what receptors does glutamate bind to
GPCRs, AMPA and NMDA
describe what happens when glutamate binds to AMPA receptors
causes fast depolarisation as the receptors are linked to Na/K channels so sodium moves into the cell.
the depolarisation also allows activation of the NMDA receptors
when do NMDA receptors become activated
when glutamate binds and when the neurone is depolarised due to AMPA receptors
what does activation of NMDA receptors lead to
opening of calcium channels leads to calcium influx
