SYNAPTIC TRANSMISSION Flashcards
what are the components of the synapse?
dendrites
soma
axon
axon terminal
what proteins are important in the presynaptic density that carry on the role of holding vesicles in place at the synapse and prevent the vesicles from fusing with the cell membrane?
actin and synapsin
what calcium channels are found in the synapse? how can this blocked/
N-type Ca++ channels
omega-conotoxin
what is the link between the AP and the exocytosis?
Ca++
what is the type of gradient used for the influx of calcium into the terminal bouton? the calcium can bind to this protein what inactivates the channels?
electrochemical gradient
calcineurin
what does there ca++ bind to? and the complex formed?
calmodulin
calmodulin dependent protein kinase (CAM-KINASE II)
what does CAM-KINASE II phosphorylates? what is the effect?
synapsin I
allows for the fusion of the vesicles to the membrane and so this protein no longer tethers vesicles to actin resulting in actin bundling. In addition, a membrane bound protein is activated by the calcium which acts as a docking station for exocytosis.
what prevents the pre synaptic site from expanding?
synaptic vesicle recycling
what is the effect of NT release?
it can bind to post synaptic receptors
it can diffuse into the blood (washout) only in the PNS not really the CNS
metabolized to a different structure
repumped into the axon terminal
what is necessary to bring about change between a NT and receptor?
effector
what channel is the effector often associated with? what type of channel is this? name the examples?
ionophore or ion channel
ligand gated not voltage gated, not so selective
EPSP - K+, Na+
IPSP- Cl-
how do summation of post synaptic potentials lead to generation of action potentials?
temporal summation
spatial summation
T/F, summation of APs is NOT possible because of the absolute refractory period?
T
most EPSPs are generated where? IPSPs
dendrites
soma
what are the requirements of IPSPs?
move a shorter distance
lose less charge
negate several EPSPs
