Term
| difference between central synapse & NMJ: reliability |
|
Definition
NMJ = a really reliable synapse (when you get one action potential you're almost always going to get a contraction in that fiber...close to 100% of the time)
central = a single excitatory input will cause an AP about 0% of the time |
|
|
Term
| difference between central synapse & NMJ: junctional folds |
|
Definition
central = do not have junctional folds (less dense)
NMJ = have folds with a ton of ACh receptors (why it's so reliable!) |
|
|
Term
| difference between central synapse & NMJ: neurotransmitters |
|
Definition
NMJ = ACh is primary (only)
central = many different neurotransmitters (ex. glutamate) |
|
|
Term
| difference between central synapse & NMJ: language regarding currents/potentials |
|
Definition
NMJ = end plate potentials/currents (EPP, EPC)
central = postsynaptic potentials, currents (EPSP, IPSP, EPSC, IPSC) |
|
|
Term
| difference between central synapse & NMJ: connection |
|
Definition
NMJ = neuron to muscle
central = neuron to neuron |
|
|
Term
| most common excitatory neurotransmitter in the brain |
|
Definition
|
|
Term
|
Definition
| loads glutamate into a transmitter |
|
|
Term
|
Definition
| do glutamate re-uptake into astrocytes or presynaptic terminal |
|
|
Term
| glutamate is made in the cell from ______ |
|
Definition
|
|
Term
| Where do the names for ionotropic glutamate receptors come from? |
|
Definition
| the other ligands that activate them |
|
|
Term
| Are there metabotropic glutamate receptors? |
|
Definition
|
|
Term
| shared structure between the different types of glutamate receptors |
|
Definition
| 4 subunits that make up the staves; each subunit has 3 domains (amino-terminal, ligand-binding, & TMR); M1 - M4 make up the TMR domain of each subunit |
|
|
Term
| glutamate receptors: ligand binding --> ? --> channel open |
|
Definition
|
|
Term
| what does a glutamate receptor kind of look like? |
|
Definition
|
|
Term
| 3 types of ionotropic glutamate receptors (ligand-gated ion channels) |
|
Definition
|
|
Term
| What is another name for metabotropic glutamate receptors? |
|
Definition
| g-protein coupled receptors |
|
|
Term
|
Definition
| loss of receptor responses during continued presence of a ligand |
|
|
Term
| Glutamate receptors quickly open, but despite continued glutamate presence, the macroscopic current bumps back to resting state indicating ______ of individual channels |
|
Definition
|
|
Term
| Desensitization controls ______ in the presence of glutamate |
|
Definition
| the amount of time receptors are open |
|
|
Term
| Are desensitization & deactivation the same thing? |
|
Definition
|
|
Term
| AMPA receptors are composed of _______ subunits (some combination of these) |
|
Definition
|
|
Term
| Do AMPA receptors have fast or slow activation, deactivation, & desensitization? |
|
Definition
|
|
Term
| AMPA receptors mediate the majority of _____ |
|
Definition
| fast excitatory neurotransmission |
|
|
Term
| Most ______ are about equally permeable to potassium & sodium with reversal potential at about 0 mV |
|
Definition
|
|
Term
| Why do AMPARs have a linear IV plot (for calcium impermeable AMPA receptors)? |
|
Definition
| they aren't voltage dependent with a reversal potential around 0 |
|
|
Term
| kainate receptors are similar to ______ electrophysiologically |
|
Definition
|
|
Term
| What is the primary function of kainate receptors? |
|
Definition
|
|
Term
| Kainate receptors are grouped with AMPA receptors in the _____ family of ionotropic glutamate receptors |
|
Definition
|
|
Term
| NMDA receptors must must contain the _____ subunit |
|
Definition
|
|
Term
| The _____ subunit of NMDA receptors bind glutamate |
|
Definition
|
|
Term
| The ______ & ______ subunits of NMDA receptors bind co-agonists |
|
Definition
|
|
Term
| How do the different GluN2 subunit types (NMDA receptors) mainly differ? |
|
Definition
| in their decay properties (desensitization) |
|
|
Term
| 2 parts of the coincidence detection of NMDA receptors |
|
Definition
1. depolarization
2. glutamate present |
|
|
Term
| At normal resting potentials (hyperpolarized), _______ can enter the NMDA receptor pore when they are open but cannot pass through --> forms a block |
|
Definition
|
|
Term
| What region of the NMDA receptor lines the pore? |
|
Definition
|
|
Term
| Asparagine (N) in the M2 region of the NMDA receptor allows _____ to pass through but not _____ |
|
Definition
| allows conductance of calcium but not magnesium |
|
|
Term
| Why is the Q/N/R site on the M2 region of the NMDA receptor named as such? |
|
Definition
| those are the amino acids that can be present on the M2 region |
|
|
Term
| What does an NMDA receptor IV plot look like for the ones with magnesium block? |
|
Definition
| there is a dip at hyperpolarized current (not just a flat line) |
|
|
Term
| What does the IV plot for NMDA receptors without a magnesium block look like? |
|
Definition
|
|
Term
| How do NMDA receptors with a magnesium block compare with NMDA receptors without a magnesium block in terms of their IV plots? |
|
Definition
| line up pretty much exactly at depolarized voltages |
|
|
Term
| NMDAR conduct only when the cell is already _____ |
|
Definition
|
|
Term
| NMDAR require a "coincidence" of what two things? |
|
Definition
| post synaptic depolarization & glutamate |
|
|
Term
| 3 things NMDAR are important for |
|
Definition
1. learning
2. memory
3. development |
|
|
Term
|
Definition
| increase in synaptic strength after high frequency stimulation |
|
|
Term
| ______ influx through NMDAR activates signaling cascades that increases the number of receptors in the synapse |
|
Definition
|
|
Term
| Is LTP only caused by NMDA stuff? |
|
Definition
|
|
Term
| What is the saying associated with NMDARs & development? |
|
Definition
| "fire together, wire together" |
|
|
Term
| As synapses start to form, NMDA receptors can start to _____ |
|
Definition
|
|
Term
| NMDARs' role in development may be similar to _____ |
|
Definition
|
|
Term
|
Definition
| cell death usually caused by too much calcium that can happen due to over activation of NMDARs |
|
|
