Term
| 3 bad consequences for if we only had excitatory neurotransmission |
|
Definition
1. seizures
2. cytotoxicity
3. a lot of tetanus |
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|
Term
| Is inhibition necessary for neuronal function? |
|
Definition
|
|
Term
| What is fast inhibitory neurotransmission for? |
|
Definition
| to prevent a neuron from firing an action potential |
|
|
Term
| Is inhibition necessarily a hyperpolarization? |
|
Definition
|
|
Term
|
Definition
| increase tendency for cell to fire APs |
|
|
Term
|
Definition
| decrease tendency for cell to fire APs |
|
|
Term
| What is the easiest way to inhibit neurons? |
|
Definition
| increase permeability to chloride |
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|
Term
| 2 main inhibitory NTs in the brain |
|
Definition
| glycine & GABA (most common) |
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|
Term
| There are many similarities between nAChR structure & GABA receptor structure...what two parts must be different? |
|
Definition
1. the ligand-binding site must be different (one binds ACh & one binds GABA)
2. the M2 region (pore lining region that confers selectivity) |
|
|
Term
| 2 ionotropic GABA receptors (fast inhibitory neurotransmission) |
|
Definition
|
|
Term
| Cell at -90 mV, opening AMPA receptor will ______? |
|
Definition
| cause inward current (we know this because reversal potential is at 0 mV) --> deep EPSC |
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|
Term
| cell at -50 mV, opening AMPA receptor --> ? |
|
Definition
| (inward current) --> weaker negative EPSC than if cell was at -90 mV |
|
|
Term
| cell at 0 mV, opening AMPA receptor --> ? |
|
Definition
|
|
Term
| cell at +50, opening AMPA receptor --> ? |
|
Definition
| (outward current) --> positive EPSC |
|
|
Term
| Why is AMPA receptor excitatory? |
|
Definition
| reversal potential is at 0 mV & AP threshold is normally around -40 mV |
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|
Term
| Excitatory synapses use ______ as a neurotransmitter |
|
Definition
|
|
Term
| Glutamate receptors have reversal potential = ? |
|
Definition
|
|
Term
| Between resting membrane potential & AP threshold sodium influx through synaptic channels is ______ |
|
Definition
|
|
Term
| Weak presynaptic stimulation of a glutamatergic synapse --> ? |
|
Definition
| weak EPSP but not to threshold |
|
|
Term
| Strong presynaptic stimulation of a glutamatergic synapse --> ? |
|
Definition
|
|
Term
| Cell at -75, opening GABA receptors --> ? |
|
Definition
| (chloride outward) --> positive IPSP |
|
|
Term
| Cell at -60, opening GABA receptors --> ? |
|
Definition
| no chloride movement/no IPSP |
|
|
Term
| Cell at -50, opening GABA receptors --> ? |
|
Definition
| (chloride inward) --> slightly negative IPSP |
|
|
Term
| Cell at -30, opening GABA receptors --> ? |
|
Definition
| (chloride inward) --> deep negative IPSP |
|
|
Term
| Inhibitory synapses use ______ as a neurotransmitter |
|
Definition
|
|
Term
| Between reversal potential & the AP threshold, net chloride influx through synaptic channels ______ the neuron & pulls it away from threshold |
|
Definition
|
|
Term
| strong presynaptic inhibition --> ? |
|
Definition
| IPSPs pulling cell away from AP threshold --> no AP |
|
|
Term
| What it means for a cell to be inhibitory = ? |
|
Definition
| preventing a cell from reaching threshold |
|
|
Term
| 2 cases where GABA(A) could be excitatory instead of inhibitory |
|
Definition
1. if action potential threshold became really low, there is a possibility where the reversal potential of chloride could be above threshold
2. if you change the equilibrium potential of chloride (make extracellular chloride really low or make intracellular chloride really high) |
|
|
Term
| threshold > membrane potential > GABA reversal potential --> ? |
|
Definition
|
|
Term
| threshold > GABA reversal potential > membrane potential |
|
Definition
|
|
Term
| GABA reversal potential > threshold > membrane potential |
|
Definition
| excitatory depolarizing IPSP |
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