Test 2: lecture 20-21

Question 1

what are the most common neurotransmitters

Answer 1

glutamate, gaba, glycine

Question 2

gluatamte is the major — neurotransmitter

Answer 2

excitatory (allows + into the cell → depolarization)

Question 3

what are the three major classes of ionotropic glutamate receptors

Answer 3

NMDA
Kainate
AMPA

Question 4

all ionotropic glutamate receptors are — channels

Answer 4

cation (allow + through, let K out and Na into the cell)

are excitatory- will cause depolarization of the cell

Question 5

ketamine will block

Answer 5

NMDA ionotropic glutamate receptor

will stop depolarization (calm it down)

Question 6

too much glutamate will do what to neurons

Answer 6

cause cell death!

Question 7

how can glutamate lead to neurotoxicity and cell death

Answer 7

glutamate allows Na into a cell and K out, if too active the increase in Na will cause H20 to come into cell and cause swelling → cell lysis

can also cause delayed apoptosis

Question 8

how is glutamate removed from the synapse

Answer 8

reuptake by ecitatory amion acid transporters (EAATS)

glial cells will also reuptake glutamate, turns it into glytamine and brings it back to presynaptic neuron for recycling

Question 9

Excitatory Amino Acid Transporters (EAATs) are powered by —

Answer 9

electrochemical gradient (Na/K)

glutamate will cause Na into the synapse, K into the cell

will pull glutamate back into presynaptic neuron for recycling

Question 10

how does ischemia effect NMDA activation

Answer 10

decreased blood flow= loss of Na/K pump= loss of membrane potention in the synapse

no potential means glutamate released will not reuptake by EAATs- this leads to prolonged NMDA activation → too much Na into the cell → swelling → cell death

Question 11

domoic acid

Answer 11

toxin in marine algae

agonist for kainate receptor (type of ionotropic glutamate receptor)

leads to headache, confusion, muscle weakness and coordination deficits

the BIRDS

Question 12

— is the major inhibitor neurotransmitter in CNS. and is used for inhibitory control of —

Answer 12

GABA

Important in inhibitory control of interneurons

Question 13

GABA is made from

Answer 13

glutamate

glutamic acid decarboxylase (GAD)

neuron can not release both GABA and glutamate= one or the other

Question 14

reuptake of GABA

Answer 14

same as glutamate

by GABA specific EAAT and glial cells

Question 15

two types of GABA receptors

Answer 15

Question 16

GABA A receptors are —

Answer 16

Cl- channels

allow Cl into the cell= inhibitory = hyperpolarization

Question 17

GABA B receptors are —

Answer 17

G protein coupled

are connected to K+ channels (move K+ out of cell) to cause membrane hyperpolarization

inhibitory

Question 18

benzos bind to what receptors and will do what?

Answer 18

bind to GABA A receptors

make it easier to channel to open= increases Cl- into the cell = inhibitory/ hyperpolarization of the cell

benzodiazepam (valium), alprazolam (xanax)

Question 19

barbiturates bind to what receptors and will do what?

Answer 19

bind to GABA A receptors

channels stay open longer= increases Cl- into the cell = inhibitory/ hyperpolarization of the cell

barbiturate= phenobarbital

Question 20

what are some barbiturates?

Answer 20

sodium amytal, pentobarbital, phenobarbital

Question 21

what are barbiturates used for in vet med

Answer 21

sodium amytal, pentobarbital, phenobarbital

used for sedation, anesthesia, and seizure control depending on the duration of action by the drugs.

causes respiratory depression in high dose = euthanasia

barbiturates bind to GABA A receptors and make them open longer allowing more Cl- into cell → inhibitory

Question 22

what are some bad symptoms of barbiturate use

Answer 22

can cause confusion, imparied judgment and slow reflexes

lethal at high dose→respiratory depression

high tolerance

bad withdrawal

easily and commonly abused

sodium amytal, pentobarbital, phenobarbital - used for sedation, anesthesia, and seizure control in animals

binds to GABA A receptors and make them stay open longer= inhibitory

Question 23

what are some Benzodiazepines

Answer 23

diazepam (Valium®), alprazolam (Xanax®).

Question 24

what are benzos used for

Answer 24

Short-acting BDZs used primarily as anxiolytics.

Long-lasting BDZs used as anxiolytics, muscle relaxants, anti-convulsants.

diazepam (Valium®), alprazolam (Xanax®).
bind to GABA A, and increased probablity of opening = inhibitory

Question 25

glycine is an --- neurotransmitter

Answer 25

inhibitory

Question 26

where can you find glycine receptors

Answer 26

medulla and spinal cord inhibitory interneurons

Question 27

what will glycine do

Answer 27

will bind to ionotropic receptors and will open **Cl channels** allows Cl- into the cell→ **inhibitory**

Question 28

strychnine

Answer 28

acts as competitive antagonist of glycine plant from asia if you have strychnine, you need more GABA to get to the same response

Question 29

how are peptide transmitter made

Answer 29

Question 30

two main classes of NT vesicles

Answer 30

**large dense core vesicles** → peptide transmitters **small synaptic vesicles** → nonpeptide transmitters

Question 31

how are large dense core vesicles made vs small synaptic vesicles

Answer 31

large: made in soma of neuron and transported down axon to nerve terminal small: made "on site" neurotransmittings already in the nerve terminal are packaged into vesicles

Question 32

if a nerve contains a classic neurotansmitter, can it also have peptide neurtransmitters?

Answer 32

yes usually only 1 classical NT per nerve, but can have a bunch of peptide NT

Question 33

peptide transmitters typically acts via --- receptors. Generally modulate ion channels activity --- via G-proteins.

Answer 33

G-protein coupled indirectly ## Footnote often slow transmission, with longer range response (can travel to new synapse), and longer lasting

Question 34

what does it mean when peptide transmitters have longer range effect

Answer 34

they are released by neuron, but can float away to other synapase and cause signal there usually slow transmission but responses generally last longer

Question 35

how does peptide NT become deactivated

Answer 35

peptidases will eat peptide NT into smaller inactive fragments

Question 36

what spinal tract carries pain to brain

Answer 36

spinothalamic tract ## Footnote responds to heat, cold, mechanical and inflammation

Question 37

--- respond to sharp, prickling, well localized and brief pain

Answer 37

Aδ fast conduction myelinated

Question 38

--- nerves respond to dull ache, diffuse, long lasting pain

Answer 38

C unmyelinated slow conduction

Question 39

nociceptors use --- as transmitters to secondary neuron

Answer 39

glutamate and substance P

Question 40

C fibers release --- Aδ fibers release ---

Answer 40

C: glutamate and substance P Aδ: glutamate only

Question 41

C fibers will release --- for small/mild stimuli

Answer 41

glutamate

Question 42

C fibers release --- for stronger stimuli and may signal persistent burning pain

Answer 42

substance P C fibers: dull, diffuse, longer lasting pain, slower non myelinated

Question 43

substance P is degraded by

Answer 43

peptidases * Neutral endopeptidase (NEP) * Angiotensin converting enzyme (ACE)

Question 44

P substance binds to what type of receptors

Answer 44

**neurokinin (tachykinin) receptors** NK1-3 maybe 4 **mostly to NK1** all are GPCR that are linked to PLC activation (IP3 and DAG as second messengers).

Question 45

NK1 receptors prefer to bind to ---

Answer 45

substance P ## Footnote neurokinin (tachykinin) receptor

Question 46

where can you find substance P

Answer 46

**skin**- pain receptor **cardio:** arterioles: cause low BP **respiratory:** bronchoconstriction (asthma?) **GI tract:** contracts GI **inflammatory:** role in immune response, helps with migration of inflammatory cells

Question 47

what does substance P do in the brain

Answer 47

Possible roles involve mood (depression), anxiety, control of respiration, nausea, and emesis

Question 48

three opioid peptide families

Answer 48

endorphins enkephalins dynorphins

Question 49

what are the three main families of opiate receptors

Answer 49

μ (mu) κ (kappa) δ (delta) **µ and κ** receptors associated with **analgesia.** **δ** receptor not as important in analgesic effects of opiates May be important for the **euphoric effects** of these drugs.

Question 50

how do opioids effect pain

Answer 50

opioids (enkephalin, endorphins, dynorphins) are released from **local inhibitory neurons** prevents release of NT(substance P and glutamate) from **primary afferent nociceptors (C fibers)**

Question 51

what will opioids do to brain

Answer 51

activated dopamine in brain cause sensation of pleasure, and mediate asaptations to stress and extreme pain

Question 52

how does nitric oxide get into cell

Answer 52

very small can just get into cells very reactive radical, with short half life

Question 53

Nitric oxide likes to bind to

Answer 53

heme will bind even better then oxygen

Question 54

what is a nitric oxide receptor and what happens when it bind

Answer 54

NO likes to bind to heme will cause activation of **soluble guanylyl cyclase** which leads to **↑cGMP** cGMP will act as second messenger to: * stimulate protein kinase G * alter response of some ion receptors * inhibit cAMP

Question 55

how does nitric oxide gas in the brain work

Answer 55

enters **postsynaptic neuron** and causes the formation of **more NO** NO will move **retroactivly** into presynaptic neurons to cause release of **cGMP**

Question 56

NO acts on blood vessels as

Answer 56

endothelium derived relaxing factor (EDRF) causes vasodilation and drop in blood pressure