NTS

Question 1

this hypothesis states that all axon terminals of a single neuron use one and only one NT though co release of multiple transmitters has been documented?

Answer 1

Dales Hypothesis

Question 2

the first transmitters of the PNS to be discovered?

Answer 2

Ach and Norepi

Question 3

what is the general approach of NT release? T/F can be manipulated pharmacologically

Answer 3

synthesis
storage
release
presynaptic receptor
high affinity reuptake
postsynaptic receptor
transmitter metabolism
postsynaptic response

Question 4

ACh is synthesized by what enzyme? via what substrates

Answer 4

choline acetyltransferase (ChAT)

AcCoA + Choline

Question 5

where does the AcCoA come from? choline?

Answer 5

mitochondrial metabolism of pyruvate

diet and 50% of ACh production uses recycled choline following high affinity reuptake

Question 6

what terminates cholinergic transmission by degrading ACh to choline and acetate? where are these localized

Answer 6

choline esterase like acetylcholine esterase and made in the liver.

ACh synapses

Question 7

name the agent based on this effect:

ACh depletion

Answer 7

-Napthylvinyl pyridine

Question 8

name the agent based on this effect:

release vesicles, depleting number for future use

Answer 8

+B-Bungarotoxin

+Black widow spider venom (BWSV)

Question 9

name the agent based on this effect:

few vesicles released

Answer 9

-Botulinum toxin

Question 10

name the agent based on this effect:

deplete ACh because choline is scarce

Answer 10

-Hemicholinium

Question 11

name the agent based on this effect:

prolongs ACh transmission, over stimulation

2 agents that are reversible and irreversible

Answer 11

-reversibly
Neostigmine
physostigmine
(medically useful)

-irreversibly
Malathion
Nerve gas
(deadly but also useful)
myasthenia gravis

Question 12

what are is the purpose of nicotinic and muscurinic receptors and their subtypes?

Answer 12

they are found in different tissues and this allows fro more specific drugs with fewer side affects

Question 13

dopamine-DA, norepinephrine-NE, epinphrine-EPi

Answer 13

catecholamines

Question 14

what are the stages for the synthesis of catecholamines?

Answer 14

L-tyrosine
L-Dopa
Dopamine
Norepinephrine
Epinephrine

Question 15

what converts L-Tyrosine to L-Dopa?

Answer 15

tyrosine hydroxylase (cytosolic)

Question 16

what converts L-Dopa to dopamine?

Answer 16

dopa decarboxylase (in many tissues)

Question 17

what converts dopamine to norepinephrine?

Answer 17

dopamine-B-hydroxylase (inside many vesicles of cells that release NE)

Question 18

what converts norepinephrine to epinephrine?

Answer 18

phenylethanolamine-N-methyl-transferase (PNMT) (cytosolic)

Question 19

what it tyrosine hydroxylase inhibited by?

Answer 19

alpha methyl tyrosine

Question 20

what is Dopa decarboxylase inhibited by?

Answer 20

alpha methyl dopa

Question 21

what is dopamine-B-hydroxylase inhibited by?

Answer 21

diethyldithiocarbamate

Question 22

what is phenylethanolamine-N-methyl-transferase stimulated by?

Answer 22

corticosteroids

Question 23

where is epinephrine mainly found?

Answer 23

adrenal medulla and brainstem

Question 24

what causes the release of NTs?

Answer 24

elevated intracellular Ca++

Question 25

what agent depletes the transmitters?

Answer 25

alpha methyl tyrosine alpha methyl dopa diethyldithiocarbamate

Question 26

what agent displaces NT from vesicles, causing initial release but long term depletion? for DA

Answer 26

amphetamines alpha-OH-butyrate for DA

Question 27

this is a stress hormone that enhances epi synthesis in the adrenal medulla?

Answer 27

cortisol

Question 28

this increase NE in the cleft and leads to long term NE depletion?

Answer 28

cocaine

Question 29

this enhances NE in the cleft?

Answer 29

desipramine and other tricyclic antidepressants

Question 30

this is a toxic compound taken up and destroys the terminal? this is used to produced Parkinsonism in animals

Answer 30

6-OH-dopamine

Question 31

this leads to long-lasting NE depletion in vesicles

Answer 31

reserpine

Question 32

what enzymes are used to produce VMA(NE and EPI) and HVA (DA)? found in the urine

Answer 32

monoamine oxidase catechol-o-methyl transferase

Question 33

catechol-o-methyl transferase (COMT) inhibitor?

Answer 33

tropolone

Question 34

what is the effect of MAO inhibitors?

Answer 34

it increases the DA, NE, EPI in nerve terminals and allows for more incorporation into vesicles so more NE enters the vesicles and more NE is released

Question 35

what are MAOI's used for?

Answer 35

antidepressants and blood pressure regulators

Question 36

where are the cell bodies of the noradrenergic neurons found?

Answer 36

locus coeruleus of the 4th ventricle

Question 37

where are the dopaminergic cell bodies found? axons tract

Answer 37

substantia nigra of the midbrain and most axons go to the corpus striatum (caudate and putamen) via the niagrostriatal tract

Question 38

what causes degeneration of the niagrostriatal tract?

Answer 38

MPTP

Question 39

what is MPTP an analog of what drug?

Answer 39

meperdine

Question 40

some DA neurons projet to the forebrain, what drugs specifically target synapses by blocking transmission?

Answer 40

antipsychotic drugs like haloperidol or chlorpromazine

Question 41

what is the other name for 5-hydroxytryptamine or 5-HT?

Answer 41

serotonin

Question 42

where is serotonin synthesized from?

Answer 42

L-tryptophan

Question 43

what ceases the serotonin transmission?

Answer 43

Na+ dependent high affinity reuptake by axon terminals and glia

Question 44

what are the serotonin inhibitors? what is the effect

Answer 44

clomipramine imipramine (prozac) fluoxetine (Zoloft) trazodone tranylcypromise act to enhance serotonergic transmission and have been used in treating depression, OCD and others

Question 45

what is sertonin transmission involved in?

Answer 45

eating, sleep, sexual behavior, circadian rhythmicity, neuroendocrine function and affect

Question 46

how many classes of serotonin receptors are there? what are the effects

Answer 46

4 major classes 5 HTI-5 HT4 increase or decrease cAMP increase or decrease K+ permeability stimulate ligand gated ionophore

Question 47

what is the primary excitatory NT of the CNS?

Answer 47

glutamate

Question 48

what has glutamate been implicated in?

Answer 48

epilepsy, brain damage and learning

Question 49

what terminates the glutamate transmission?

Answer 49

Na+ dependent high affinity reuptake by the neurons and glia

Question 50

what are the 4 classes of glutamate receptors? which ones are ionotropic and metabotropic?

Answer 50

NMDA AMPA Kainate ionotropic ACPD (increase Ca2+) AP4 (decrease cAMP, cGMP) metabotropic

Question 51

what are the inhibitory NTs?

Answer 51

GABA and glycine

Question 52

this is the main inhibitory NT of the brain, GABA released by what? lowered gabaergic transmission is implicated in?

Answer 52

GABA interneurons Huntington's disease, epilepsy, tardive dyskinesia, alcoholism, schizophrenia, and sleep disorder

Question 53

what is GABA synthesized from?

Answer 53

glutamate by glutamic acid decarboxylase

Question 54

what are the GABA receptor types? name the agonists and antagonist?

Answer 54

GABA A and B GABA A best characterized +isoguvacine -bicuculline GABA B involved in presynaptic inhibition +baclofen -phaclofen

Question 55

what do the GABA A receptors have binding sites for?

Answer 55

barbiturates and benediazepine

Question 56

what stimulates the benediazepine site?

Answer 56

diazepam

Question 57

what stimulates the barbiturate site?

Answer 57

phenobarnitol pentobarbitol Cl- channel

Question 58

what stimulates and inhibits the GABA site?

Answer 58

muscimol (hallucinogenic mushroom) stimulates bicuculline (a convulsant)

Question 59

what enhances the Cl- conductance at the channel and depresses?

Answer 59

ETOH Benzos and Barbs

Question 60

what is the principal inhibitor of the spine?

Answer 60

glycine, this opens the Cl- channel to produce IPSP and is inactivated by reuptake causing skeletal muscle to not contract

Question 61

what are the glycine agonist and antagonist?

Answer 61

agonist: other amino acids not GABA antagonist: strychnine (muscles contract)