Intro to Neuroscience Flashcards
Function of Schwann Cell?
PNS Myelinate 1 neurone Axon regeneration Secrete NGF Secrete Laminin Phagocytosis (of myelin)
Function of Astrocytes?
Maintain CNS environment (K+, glutamate)
Structure
Inhibit regeneration
Phagocytosis
Function of oligodendrocytes?
CNS
Myelinate >40
inhibit regeneration
phagocytosis
Function of Microglia?
immune cells of CNS
AIDS - Tlymph - brain
Function of ependymal cells?
Line ventricular system
Subependymal - neuronal stem cell population
3 meninges?
1) Dura mater - supports brain
2) Arachnoid Mater
[Subarachnoid space]
3) Pia mater - astrocytes mainly``
Generator Potential
aka receptor potential.... Initiate AP in neuronal axon Associated with non specific cation channels modality specific GRADED potentials transient or sustained DONT contain modality specific info!
AP
Electrical signal passing along axon
ALL OR NOTHING
Frequency and pattern encoding
Must be hypopolarised to start and reprimed
EPSP
Contribute to somatic depolarisation GRADED Normally fast - ligand gated ion channel Diff NT acts on same cell at diff receptors Metabolically expensive vunerable to drugs
IPSP
Prevent somatic depolarisation
GRADED
Normally fast - ligand gated anion channel
by GABA - glycine
Diff NT acts on same cell at diff receptors
Metabolically expensive
vunerable to drugs
Events as AP arrives at presynaptic terminal?
Pre AP…Ca++ current…Exocytosis…Evoked postsynaptic current…post synaptic AP
3 pools of vesicles in active zone?
Readily releasable - tethered to proteins associated to presynaptic membrane
Reserve - replace those in RR
Resting - tethered further away
How long for 1 vesicle to go through presynaptic vesicle cycle?
40 seconds
V/T snare interaction??
V snare - VAMP/synaptobrevin
T snare - syntaxin/snap25
Association = nucelation = zippering = fuse = exocytosis
Synaptotagmin?
Ca++ sensor…C2A and C2B bind Ca++ and insert into membrane
