Lecture 7 Flashcards
T or F? Exc or Inh inputs can be received in a dendrite.
T
Why is the AP threshold lowest at the trigger zone?
more Na channels
T or F? Exc or ing inputs decrease in time.
T
T or F? The threshold for each cell is constant for all surfaces of the cell.
F. Lower threshold at the trigger zone (more Na channels)
What determines relative efficacy of input to create an AP?
proximity to synapse
T or F? A distal synapses with the same level of exc input will have a greater impact than one that is more proximal.
F. vice versa
How are synaptic potentials integrated?
spatially and temporally
These are the dominant player after threshold is reached?
Voltage gated Na channels
EPSP’s are used in reference to __ and EPP’s are used in reference to:
CNS, NMJ
EPSP’s are triggered by ___ and EPPs are triggered by:
glutamate, AcH (and glutamate)
Why can synaptic pot’s increase temporal?
build up of Ca bc they don’t have time to close completely
The buildup of _____ leads to temporal summation of synaptic potentials:
Ca
There ___ times more Ca outside the cell than inside.
10,000
Why will low freq stimulation generate the same size EPSP?
Ca had time to return to baseline
T or F? Spatial and temp can only happen with EPSP .
F. Both EPSP and IPSP
Can inhibition be presyn, postsyn, or either.
either
Postsynaptic inhibition is mediated by:
GABA(aR)
What molecule is used in postsynaptic inhibition?
Cl- (GABA is a chloride channel)
What affect postsyn inhibition have on an EPSC?
shunt and reduce the efficacy
Where are postsyn inhibitory synapses located?
dendritic shaft of cell body near AP trigger zone
T or F? Inhibitory synapses can only work locally.
T
T or F? Inhibitory synapses can decrease the efficacy of excitatory inputs over the whole cell globally.
T
Where does presynaptic inhibition usually occurs?
at axon-axonic synapse
What does it mean if you decrease the efficacy of an EPSP?
size decreases
What type of channel does presynaptic inhibition target?
Ca channels
What type of receptor is involved with presynaptic inhibition?
GABA(b)
What type of receptor is GABA(b)?
metabotropic receptor