Neurophys Basis Of Beh; Neurotransmitters

Front 1

Role of ependymal cells

Back 1

Glia that provide lining for fluid-filled ventricles in brain

Front 2

Role of microglia

Back 2

Glia that serve as phagocytes to remove debris left by dead or degenerating neurons/glia

Front 3

The Na/K/ATPase moves ___ sodium ions out of the cell for ____ potassium ion in.

Back 3

2;1

Front 4

Three basic categories of neurotransmitters

Back 4

Biogenic amines

Amino acids

Neuropeptides

Front 5

The method by which the amino acid neurotransmitters (generally) generate an action potential.

Back 5

Directly opening or closing ion channels. (ligand-gated)

Front 6

Two main 2nd messenger systems

Back 6

1) Adenylate cyclase system

2) Phosphoinositide system

Front 7

What happens in the adenylate cyclase 2nd messenger system?

Back 7

1) Neurotransmitter binds receptor and activates one of a family of G proteins named for affinity for GTP.

2) GTP either stimulates or inhibits adenylate cyclase. Gs protein causes stimulation and Gi protein causes inhibition.

3) If adenylate cyclase is inhibited, NO AP is generated.

4) If adenylate cyclase is stimulated --> cAMP is produced --> cAMP closes K+ channels which causes depolarization.

Front 8

What happens in the phosphoinositide system?

Back 8

1) Binding of a receptor by a neurotransmitter activates G protein that activates phospholipase C. (PLC)

2) PLC hydrolyses a membrane phospholipid into two second messengers which in turn blocks calcium activated potassium channels.

4) Net effect - less K+ released from neuron, raising electrical charge within neuron and causing depolarization.

Front 9

List catecholamines

Back 9

Dopamine

Norepinephrine

Epinephrine

Front 10

List indoleamines

Back 10

Serotonin

Front 11

List quaternary amines

Back 11

acetylcholine

Front 12

______ is principally located in PNS and has a minimal role in CNS neurotransmission

Back 12

EPI

Front 13

______ is principally located in PNS and has a minimal role in CNS neurotransmission

Back 13

EPI

Front 14

Catecholamines are synthesized from amino acid ______

Back 14

tyrosine

Front 15

What is the rate-limiting step for synthesis of catecholamines?

Back 15

Tyrosine hydroxylase (the conversion of tyrosine to L-DOPA)

Front 16

What is the cofactor for tyrosine hydroxylase?

Back 16

tetrahydrobiopterin.

Front 17

Converts L-DOPA --> Dopamine

Back 17

DOPA decarboxylase

Front 18

Converts Dopamine --> NE

Back 18

Dopamine β-hydroxylase

Front 19

Converts NE-> EPI

Back 19

Phenylethanolamine N-methyltransferase

Front 20

Four major dopamine pathways

Back 20

1) nigrostriatal tract
2) mesolimbic-mesocortical tract
3) tuberoinfundicular tract
4) chemoreceptor trigger zone

Front 21

Nigrostriatal tract of DA; what is the purpose?

Back 21

Role of DA is in initiation of movement.

Front 22

Nigrostriatal tract of DA; what is the pathway?

Back 22

Neurons originate within the cell bodies of the substantia nigra and terminate in the caudate and putamen (aka striatum).

Front 23

Tuberoinfundibular tract of DA: what is purpose?

Back 23

Links hypothalamus to anterior pituitary gland where DA inhibits release of prolactin. Prolactin levels give a rough indication of dopaminergic activity.

Front 24

____levels give a rough indication of dopaminergic activity because dopamine inhibits its release.

Back 24

Prolactin (more prolactin means less dopamine)

Front 25

Mesolimbic-mesocortical tract of DA: what is purpose?

Back 25

Sensation of pleasure, influences reasoning and modulates emotions and emotionally driven behavior.

Front 26

Mesolimbic-mesocortical tract of DA: what is pathway?

Back 26

Origin: midbrain near substantia nigra

Projection: to limbic system and frontal cortex

Front 27

Chemoreceptor trigger zone is an area in the brainstem, rich in DA, neurons, that when stimulated produces _______

Back 27

nausea and vomiting

Front 28

What is the D1 receptor responsible for?

Back 28

Increases adenylate cyclase activity, required for stimulant effect of cocaine

Front 29

Action of DA is primarily terminated by _______

Back 29

reuptake

Front 30

What are the enzymes that degrade DA?

Back 30

Monoamine oxidase (MAO)

Catechol-o-methyl transferase (COMT)

Front 31

__________ is the product of DA catabolism that, in the CNS, gives a rough indication of DA activity

Back 31

homovanillic acid

Front 32

The ___ receptor is responsible for the typical antipsychotic effects (therapeutic and extrapyramidal)

Back 32

D2

Front 33

The ___ receptor is responsible for the atypical antipsychotic effects

Back 33

D4

Front 34

In the striatum, DA is in equilibrium with ______

Back 34

ACh

Front 35

Main cluster of NE containing cell bodies is in what area?

Back 35

Locus ceruleus

Front 36

What is the primary role of NE?

Back 36

Neuroregulatory role.

1) Sleep: NE neurons are silent
2) Attention and Concentration: NE neurons are active in startling situations
3) Mood: NE is inhibited in depressive states

Front 37

Role of α2 NE (adrenergic) receptors

Back 37

Decrease adenylate cylcase activity on presynaptic neuron. When NE binds it is inhibitory to the presynaptic neuron.

Agonists are sedative and antihypertensive.

Front 38

Clonidine: MOA

Back 38

α2 agonist

Front 39

NE is broken down by what enzymes?

Back 39

monoamine oxidase and COMT

Front 40

Serotonin (5HT) is synthesized from what amino acid?

Back 40

Tryptophan, which is taken up into the brain via a saturable active carrier mechanism

Front 41

Serotonergic pathways originate from the ______ nucleus

Back 41

raphe

Front 42

What is the rate limiting step of 5HT synthesis?

Back 42

tryptophan hydroxylation by tryptophan hydroxylase.

Front 43

what is the general role of serotonin?

Back 43

widespread behavioral suppression. generalized arousal, sexual interest, aggression, ability to pursue goal-directed activities.

Front 44

What is the special role of 5HT in spinal cord?

Back 44

5HT influences enkephalinergic and substance P neurons, thereby reducing the perception of pain.

Front 45

Role of the 5HT-1A receptor subtype

Back 45

Antidepressant action. Where buspirone is a partial agonist.

Front 46

Buspirone is a partial agonist of what 5HT receptor subtype?

Back 46

5HT-1A

Front 47

Role of the 5HT-2A receptor subtype

Back 47

Target of hallucinogens and atypical antipsychotics (along with D4)

Front 48

Role of the 5HT-2C receptor subtype

Back 48

Regulation of appetite, anxiety, seizures, target of hallucinogens and antypical antipsychotics

Front 49

Role of the 5HT-6 receptor subtype

Back 49

Target of hallucinogens and atypical antipsychotics

Front 50

Main metabolic pathway of 5HT involves prodution of what metabolite, which is an indicator of 5HT CNS activity?

Back 50

5-HIAA

Front 51

Acetylcholine synthesis occurs trhough the combo of __ and ___

Back 51

choline (diet and liver) and acetyl radical (from Acetal CoA)

Front 52

ACh is hydrolyzed by AChE to _ and __

Back 52

choline and acetate

Front 53

What is the nucleus basalis of meynert?

Back 53

Major collection of forebrain cholinergic neurons, plays a major role in memory.

Front 54

2 classes of cholinergic receptors

Back 54

nicotininic, muscarinic

Front 55

Role of the M1 receptor subtype

Back 55

regulation of cognition, involvement in seizures

Front 56

Role of the M4 receptor subtype

Back 56

Target of antiparkinsonian anticholinergic drugs

Front 57

Two GABA receptors

Back 57

GABA-A and GABA-B

Front 58

Site of action of benzodiazepines

Back 58

GABA-A

Front 59

How are neuropeptide neurotransmitters different from others neurotransmitters?

Back 59

1) Made in cell body and then transported to bouton

2) Tend to be linked with classic neurotransmitters (eg, monoamines) in their functioning

3) Require <b>high frequency stimulation</b> for release

Front 60

What happens when neuropeptides bind a receptor?

Back 60

They increase the affinity of that receptor for a monoamine. When the monoamine binds, a second messenger system is invoked.

Front 61

Endogenous substances that all share some morphine-like pharmacological property

Back 61

opioid peptides

Front 62

What is proopiomelanocortin (POMC)? What is it converted to?

Back 62

A precursor protein that is converted to ACTH, Melanocyte stimulating hormone (MSH), and beta-endorphin

Front 63

What is proenkephalin? What is it converted to?

Back 63

Met and Leu enkephalin

Front 64

What is prodynorphin? What is it converted to?

Back 64

beta-neoendorphin;

dynorphin

Front 65

What is substance P and where is it found?

Back 65

A neuropeptide that modulates the sensory transmission of pain in the DRG of spinal cord.