5. Neurotransmitters and Receptors (Pharm) Flashcards
(97 cards)
1
Q
2 types of receptors we are concerned with in neuro pharm?
A
ionotropic, metabotropic
2
Q
inflow of what ions will cause a cell to depolarize?
A
Na and Ca2+
3
Q
inflow of what ion will cause a cell to hyperpolarize?
A
Cl-
4
Q
outflow of what ion will cause a cell to hyperpolarize?
A
K+
5
Q
neurotransmitters modulate what part of the action potential?
A
the resting membrane potential
6
Q
neurotransmitters + receptors: short term changes are what?
A
changes in the membrane potential or postsynaptic cell
7
Q
neurotransmitters + receptors: long terms changes via what?
A
activation of signaling cascades
8
Q
IPSP stands for what?
A
inhibitory post synaptic potential
9
Q
EPSP stands for what?
A
excitatory post synaptic potential
10
Q
T/F: ionotropic receptors involve direct opening of ion channels
A
T
11
Q
T/F: G-protein coupled receptors can be both ionotropic and metabotropic
A
F
12
Q
T/F: Secondary messengers are required for signaling through metabotropic receptors
A
T
13
Q
T/F: Na+ and K+ commonly pass through ion channel receptors to alter membrane potential
A
T
14
Q
A few things about ionotropic receptors?
A
- Involve direct opening of channel
- Permeable to ions -> modulation of membrane potential
- Na+, K+, Cl-, Ca2+
15
Q
A few things about metabotropic receptors?
A
- Involve secondary messengers
- involve metabolic pathways
- G-Protein-coupled
16
Q
three groups of neurotransmitters?
A
amino acids, acetylcholine, monoamines
17
Q
amino acids include… (2 AAs)
A
GABA, Glutamate
18
Q
name 3 categories of monoamines and the drugs within those categories
A
Catecholamines (dopamine, NE, epi)
Histamine
Tryptamines (serotonin, melatonin)
19
Q
name a few other neurotransmitters
A
Histamine, Adenosine, Cannabinoids, Opioids, endorphins
20
Q
name 2 excitatory amino acids?
A
glutamate, aspartate
21
Q
name 2 inhibitory amino acids?
A
GABA, glycine
22
Q
what is the major excitatory NT in the CNS?
A
glutamate (green light on traffic light)
23
Q
what secretes glutamate?
A
pyramidal cells
24
Q
glutamate works in the ionotropic or metabotropic receptors?
A
both
25
what processes does glutamate play major roles in?
synaptic plasticity and learning/memory
26
excess glutamate can lead to what?
excitotoxicity (AD, ALS, neuropathic pain) - think burnout of the neurons
27
three families of ionotropic glutamate receptors?
AMPA, NMDA, kainate
28
NMDA glutamate receptor: what are antagonists?
Ketamine ("Special K"), PCP
29
NMDA glutamate receptor: requires what as a co-agonist to be activated?
Glycine
30
NMDA glutamate receptor: blocked by what?
Mg2+. Require depolarization to remove block
31
NMDA glutamate receptor: permeable to what?
Ca2+
32
NMDA glutamate receptor: critical for what?
synaptic plasticity, learning, memory
33
what is the major inhibitory NT?
GABA. CNS depressant. remember stop sign.
34
what receptors does GABA use?
GABAa, GABAb, GABAc
35
a few important GABA drugs?
Benzodiazepines, Barbituates. Alcohol, General Anesthetics
36
GABAa receptors: how many subunits?
3. different drugs bind to different subunits.
37
what is the mechanism for GABAa being a CNS depressant?
ionotropic receptor (ligand gated). GABA binds and opens Cl- channel. influx of Cl- into cell hyperpolarizes the cell and therefore prevents depolarization.
38
GABAa typically used clinically for what?
Anti-anxiety, sedative, anticonvulsant, muscle relaxant
| Treat anxiety, insomnia, seizures, alcohol withdrawal
39
GABAb receptors: ionotropic or metabotropic?
metabotropic.
40
GABAb accomplish what?
Stimulates opening of K+ Channels, close Ca2+ channels. Efflux of K+ and decrease in Ca2+ conductance causes hyperpolarization of postsynaptic membrane (Inhibition)
41
GABAc receptors do what?
Opens Cl- Channels (inhibition when Cl- flows in due to hyperpolarization)
42
GABAc receptors: ionotropic or metabotropic?
ionotropic
43
GABAc receptors: high expression where?
High expression in retina, spinal cord and pituitary
44
Acetylcholine: acts on what kind of receptors?
Nicotinic Receptors (Ionotropic –Na+)
Muscarinic Receptors (Metabotropic)
-M1-M5
-G coupled (Slower excitation)
45
what makes acetylcholine? what breaks it down?
ChAT (choline acetyl transferase) makes acetylcholine.
| AchE breaks it down.
46
Nicotinic receptors: open what channels? excitatory or inhibitory?
Opens Na+ Channels resulting in depolarization (EPSP)
47
agonists of nicotinic receptors?
Agonists:
nicotine: addictive, anxiolytic, analgesic, increases alertness
epibatidine, choline
48
Muscarinic receptors: which are found in CNS?
M1, M3, M4, M5
49
muscarinic receptors: which are found in the heart?
M2
50
muscarinic receptors: which are found in the smooth muscle?
M3
51
muscarinic receptors: what are antagonists?
atropine (M1-M5), scopolamine (M1)
52
what is the treatment/antidote for sarin/organophosphate poisoning?
atropine
53
very potent AchE inhibitors?
organophosphates. cause SLUDGE, DUMBBELSS
54
AchE inhibitors that are prescribed?
Donepezil
Tacrine
Galantamine
Rivastigmine
55
what is the mechanism of action for Fluxotine?
it is a SSRI: works at the serotonin reuptake receptor and inhibits reuptake.
56
dopamine is made from what precursor?
tyrosine
57
dopamine is degraded by what?
MAO and COMT
58
re-uptake of dopamine is done by what?
dopamine transporter (DAT)
59
dopamine activates what receptors?
D1-D5
60
dopamine is produced where?
ventral tegmental area, substantia nigra
61
dopamine is involved in what sorts of behaviors?
Involved in behavior, cognition, motor activity, motivation, reward, addiction
62
the D1 family of dopamine receptors includes what receptors? inh or excit?
D1 and D5. increases adenyl cyclase: excitatory.
63
the D2 family of dopamine receptors includes what receptors? inh or excit?
D2, D3, D4. increases phospodiesterase and produces inhibitory response
64
How does Parkinson's result from insufficient dopamine?
substantia nigra degenerates, less dopa sythesized
65
treatment strategies for Parkinson's? (4)
give L-Dopa (which is a Dopamine precursor)
give COMT inhibitors
give DOPA decarboxylase (acts on DOPA to produce dopamine)
give dopamine agonists
66
give the chemical pathway that yields epinephrine from tyrosine
Tyrosine -> DOPA -> Dopamine -> norepinephrine -> Epinepnrine
67
what do antipsychotics do to the D2 receptor?
antagonize
68
what does cocaine do to the dopamine receptor?
prevents dopamine reuptake
69
what do amphetamines do to dopamine?
induce DA release
70
what does Methylphenidate do to dopamine?
reuptake inhibitor
71
norepinephrine: degraded by what?
MAO and COMT
72
norepi: reuptake by what?
NET (Norepinephrine Transporter)
73
norepi: works at what receptors? what kind of receptors are they?
Metabotropic (a1/b1 adrenergic receptors). agonist.
74
norepi: produced where?
Locus Coeruleus, Caudal Raphe Nucleus
75
norepi is main NT in what system
Main neurotransmitter in sympathetic system
76
serotonin: made from what precursor?
L-tryptophan
77
serotonin: degraded by what?
MAO
78
serotonin: reuptake by what?
SERT (Serotonin Transporter)
79
serotonin: activates what receptors?
5-HT 1-7 receptors
80
serotonin: produced by what?
raphe nucleus (pons)
81
histamine works at what receptors?
H1-H4
82
H1 is important for what?
arousal (inhibit K channels) --> Antihistamines=drowsy
83
adenosine does what to which channels?
inhibits Ca influx channels, activates K channels (antiarrythmic)
84
cannbinoids work though what receptors? what types of receptors are these?
CB1 and CB2. metabotropic (G-coupled).
85
when activated, the CB1 receptor does what?
inhibits GABA and glutamate release. effect varies depending on brain region.
86
anandamine: what does it do?
endogenous CB1 agonist. attenuates pain
87
THC: what does it do?
exogenous CB1 agonist.
88
name a few endogenous opioids?
Endorphins
Enkephalins
Dynorphins
89
name a few drugs that are opioids?
morphine, heroin, codeine
90
Baclofen is a selective agonist of what receptors?
GABAb. --> Antiplasticity in ALS and MS
91
Is this receptor-drug pairing correct? GABA-Baclofen
Yes
92
Is this receptor-drug pairing correct? 5-HT-Fluoxetine
No, fluoxetine inhibits the re-uptake receptor (SERT)
93
Is this receptor-drug pairing correct? NMDA-Ketamine
Yes
94
Is this receptor-drug pairing correct? AChR-Nicotine
Yes
95
what can levodopa do that dopamine cannot?
cross the BBB
96
what does carbidopa do?
it is a peripheral decarboxylase inhibitor - inhibits the formation of dopamine from its precursors
97
why is levodopa often administered with carbidopa?
levodopa is given to cross the BBB, and it is converted to dopamine in the brain. carbidopa is given along with it to inc the availability of L-dopa in the brain and limit peripheral side effects.
