Lecture 12 Flashcards Preview

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Flashcards in Lecture 12 Deck (44):
1

__ is needed for the formation of additional synaptic connections

gene expression

2

late phase effects are thought to be initiated by __ which activates a transcription factor (i.e. __) which stimulates the expression of other proteins ultimately leading to __

protein kinase A; CREB; the generation of new synaptic contacts

3

what happens to the EPSPs when you add an inhibitory of protein synthesis?

you see short-term potentiation instead, it goes back to normal in a matter of hours

4

protein synthesis does not affect LTP in __

early stages

5

T/F: you can't get new memories (learning, synaptic plasticity) without new neurons

FALSE

6

LTP is specific to __: just because one synapse is __ doesn't mean it will have an effect on nearby synapses.
HOWEVER LTP is also __: if one pathway is strongly stimulated and a nearby pathway is weakly (or strongly) stimulated, __

the synapse; strengthened; associative; both synapses will be strengthened

7

low frequency stimulation on just one synapse with nothing else happening nearby causes __

long-term depression

8

it is the __ that strengthens the synapse and leads to lasting changes in how signals are transferred between cells

coordinated activity between the presynaptic and postsynaptic elements

9

results of NMDA receptor knockout mice: (3)

less LTP in hippocampus
less LTD in hippocampus
slow learners in water maze

10

results of NMDA receptors mutants with increased conductance of channels: (3)

stronger LTP
fast learners in mazes
long-lasting memory

11

genetic engineering of NMDA receptors affects hippocampal __

synaptic plasticity and learning

12

at a glutamatergic synapse: during low frequency stimulation, __ is being release from the presynaptic terminal and binding to __ receptors and activating them, giving a little __, also binding to __ receptors but not activating them (because __)

glutamate; AMPA; EPSP; NMDA; we don't have a great enough EPSP to remove the magnesium)

13

at a glutamatergic synapse: at high frequency stimulation, there is a lot more __ being released from presynaptic terminal so there are more __ receptors being activated and thus more __ of the postsynaptic membrane (enough to __ allowing __ to flow into the cell)

glutamate; AMPA; depolarization of postsynaptic membrane; enough to remove the magnesium and activate NMDA receptors; calcium

14

the __ is the trigger for LTP

CALCIUM

15

we have seen experimentally that LTD perseverates in animals that have been exposed to __ __

ethanol perinatally

16

different levels of postsynaptic Ca can induce either _ or __

LTP or LTD

17

protein phosphatases basically act in the opposite way as __

protein kinases

18

early observations of glutamatergic synapses revealed that stimulation sometimes __

didn't result in a subsequent response (silent synapses)

19

silent synapses are prevalent in __ and have also been located in various areas including the __

development; hippocampus

20

the silence in silent synapses is due to __ and the fact that the postsynaptic cell of these synapses only have __

the magnesium blocking NMDA channels; only NMDA channels, no AMPA

21

as juveniles, we only have __ receptors at glutamatergic synapses, no __

NMDA; AMPA

22

hippocampal synapses: LTP enhances these, LTD comes long and diminishes this enhancement - it is this __ that is what's important - that the synapse can __

dynamic-ness; continuously be enhanced or diminished in response to stimuli

23

LTD is though to involve a __ in calcium, which activates postsynaptic __ which causes an internalization of the __ receptors and the synapse becomes __

a very low rise in calcium; phosphatases; AMPA; less sensitive

24

LTD and LTP are predicated on __

changes in the postsynaptic cell and its sensitivity

25

late stages of LTP are mediated by __

transcription

26

cell-impermeant molecules: (ex)

neurotransmitters

27

cell-permeant molecules: (ex)

hormones, steroid hormones, glucocorticoids

28

cell-associated molecules: only act when other cells are __, hang out on __

in contact with them; the membrane

29

three classes of cell signaling molecules

cell-impermeant molecules
cell-permeant molecules
cell-associated molecules

30

G-protein = __-binding protein

GTP

31

monomeric G-protein: __ interacts with receptor and binds __/__. plays a role in __ (3)

Ras; GTP/GDP; cell differentiation, development, and proliferation

32

the effect of a signaling molecule is mediated by __

the presence of its receptor

33

GAP = __. __ GTP and return G-protein to __

GTPase activating proteins; hydrolyze; inactive state

34

the binding of a signaling molecule causes __ and that triggers a subsequent __ within the cell

a conformational change in the receptor; signaling cascade

35

4 types of receptors

channel-linked receptors, enzyme-linked receptors, intracellular receptors, and G-protein coupled receptors

36

what was the first monomeric g-protein discovered?

RAS

37

monomeric (__) g-protein: relays signals from __ to a __

small; activated cell receptors; intracellular target

38

heteromeric g-protein coupled receptors: has __ subunits that interact together and with the receptor. __ subunit binds GDP/GTP. __ subunits always work together. __ or __ can be the effector.

alpha, beta, and gamma; alpha; beta and gamma; alpha or beta/gamma

39

there is lots of __ in the subunits of heteromeric g-proteins

variability (100s of combinations

40

heteromeric g-proteins have __ targets

diverse

41

heteromeric g-proteins: alpha subunit either binds to __ and becomes __ or binds to __ which causes it to __

GDP; inactive; GTP; dissociate (leave the other subunits) and go act on the effector protein

42

heteromeric g-proteins: resting state
when neurotransmitter bind to the receptor, the receptor interacts with __ subunit and exchanges __ for __
__ separates from __, either can act on effector protein
later GTP is hydrolyzed to __ by __

alpha/beta/gamma interact with each other, GDP is bound to alpha
alpha; GDP; GTP; alpha/GTP; beta/gamma; GDP; GAP

43

4 examples of neuronal second messengers

Ca, cyclic AMP, cyclic GMP, and IP3

44

cAMP activates __

protein kinase A