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Flashcards in Neurotransmitter Systems Deck (45):
0

Ach - central locations

pons
midbrain
the striatum

1

Ach - General function

Crucial in producing consciousness, but not awareness
control of voluntary motion
initiation of REM sleep

2

Ach - vesicular storage

Ach stored in clear vesicles
Moved into vesicles by VAchT

3

Ach - Catabolism

Acetylcholinesterase bound to the POST synaptic cell membrane

4

Ach Receptors (2)

nicotinic (NAchR)
muscarinic (MAchR)

5

Muscarinic receptor properties

4 or 5 different types, all activated by muscarine
serpentine receptor
GPCR

6

M1 (neuronal) MAchR

Gq
increase IP3/DAG, Increase Ca++

7

M2 (cardiac) MAchR

Gi
decrease cAMP, increase K+ efflux

8

M3 (sm m. of bronchi, vasculature, endothelial cells of vasculature) MAchR

NO
Gq
IP3/DAG, increase Ca++

in the vasculature NO is the major effector (which wins)

9

Nicotinic receptors

located at NMJ (Na), autonomic ganglia, other parts of the CNS (Ca, Na)
5 subunits
IONOTROPIC
allow for Na entrance, allthough some neuronal forms allow for significant Ca influx

10

Amino acid NTs (list)

glutamate, aspartate, taurine (EAAS)
GABA, glycine (inhibitory amino acids)

11

GABA - location

cerebellum
cortex
retina

12

GABA - functional roles

major inhibitory NT in the higher CNS
critical for producing consciousness/awareness
control of voluntary motion

13

GABA - synthesis

glutamate decarboxylase (GAD)
derived from glutamate

14

GABA - how is action limited

reuptake
catabolism by GABA transaminase

15

GABA - what does it bind to

GABA-A and GABA-B receptors

16

GABA-A receptors
ionotropic/metabotropic
subunits
ion conductance (if ionotropic)/Gprotein if metabotropic
other important chemicals

IONOTROPIC
5 subunits
Cl- conductance
benzodiazapine site potentiates

17

GABA-B receptors
ionotropic/metabotropic
subunits
ion conductance (if ionotropic)/Gprotein if metabotropic
other important chemicals

Metabotropic
-
heterodimer G protein (Gq and Gi) decreases adenylyl cyclase, increases K+ efflux. AND decreases IP3/DAG, decreases Ca influx
-

18

Many general anesthetics are now postulated to produce anesthesia by activating what receptors?

GABA receptors, mostly GABA-A, at extra-synaptic locations throughout the cortex

19

Glycine - location

spinal cord
brainstem
forebrain (less than gaba)

20

glycine - function

mediates many spinal inhibitions

21

glycine - binds to

glycine receptors

22

glycine receptor
ionotropic/metabotropic
subunits
ion conductance (if ionotropic)/Gprotein if metabotropic
other important chemicals

ionotropic
a=glycine binding, b = structural
Cl-
blocked by strychnine

23

Peptide NT (2)

opiods
endocannabanoids

coded for by genes, originally thought to be neuromodulators

24

Opiods - location

basal ganglia
hypothalamus
parabrachial nuclei and raphe nuclei

25

opiods - general functions

modification of nociceptive inputs
modification of mood/affect

26

Opioid - 4 precursor molecules

proenkephalin
pro-opiomelanocortin
prodynorphin
orphanin FQ

27

proenkephalin - sequence and 2 major variants

tyr-gly-gly-phe-x

met-enkephalin
leu-enkephalin

28

pro-opiomelanocortin (POMC)

B endorphins

29

prodynorphin

When you cut up prodynophin, it gives rise to 4 opioid molecules

3 molecules of leu-enkephalin
dynorphins (8aa or 17aa) --> a smaller form OR the larger form

30

Orphanin FQ aka?

nociceptin

31

How are opioids made?

Since they are peptides, they are made through the usual protein synthetic machinery

32

How do we limit opioid action?

enzymatic activity, possibly after reuptake
enkephalinase A and B
aminopeptidase

33

What (3) receptors do opioids bind to?

mu, kappa, delta

34

Mu receptor
receptor type and effects

serpentine
ANALGESIA, RESPIRATORY DEPRESSION, EUPHORIA
sedation, constipation

35

Kappa receptor
receptor type and effects

serpentine receptor,
ANALGESIA, DYSPHORIA
diuresis, miosis

36

Delta receptor
receptor type and effects

serpentine
ANALGESIA

37

all opioid receptors are _______ and are ______ adenylyl cyclase

serpentine receptors
inhibit
Mu - increases K+ efflux and hyperpolarizes
Kappa and delta - decrease Ca

38

The two endocannabanoids are

anadaminde
2-AG (arachydonylglycerol)

39

Anadamide

"bliss"
arachidonic acid +ethanoloamine

40

2-Arachydonylglycerol

arachadonic acid esterified into the middle, #2 position of glycerol

41

Distribution of endocannabinoids in the CNS

broad distribution
hippocampus - memory formation
Basal Ganglia - affect, motor
spinal cord - modulation of nociception
neocortex - neuroprotective (?)

42

What type of receptors do the endocannabinoids bind to? (2)

CB-1 and CB-2

43

CB-1 receptor
where
what type
what it does
what it binds

axons and presynaptic terminals of EAA and GABA synapses
Gi protein coupled receptor
reduces NT release
binds to either anadamide or 2-AG equally

44

CB -2 receptor
where
what type of receptor
additional sites found
function

found in brain MICROGLIA, not neurons
metabotropic
immune system and gut
antiinflammatory, in brain cause macrophage to remove B-amyloid