Test 4 Review

Question 0

neurotransmitters

Answer 0

signaling molecules that have specific receptors

Question 1

cell signaling

Answer 1

how cells communicate with each other, using neurotransmitters

Question 2

hydrophilic ligands have receptors located where?

Answer 2

cell surface, because these ligands are water soluble and can’t cross the lipid membrane

Question 3

hydrophobic ligands have receptors located where?

Answer 3

intracellular, because these ligands are lipid soluble and can penetrate the lipid membrane

Question 4

synapse

Answer 4

junction between two nerves where chemical signaling happens

Question 5

4 modes of cell communication

Answer 5

endocrine signaling, neuroendocrine signaling, paracrine signaling, and autocrine signaling

Question 6

endocrine signaling

Answer 6

the blood is the transporter from one cell to another

Question 7

neuroendocrine signaling

Answer 7

neuron is taken to the target by blood

Question 8

paracrine signaling

Answer 8

cells are very close together, and the message is transmitted by interstitial fluid

Question 9

autocrine signaling

Answer 9

the cell message is returned to the same cell

Question 10

steps that happen when the receptor is extracellular

Answer 10

1. the ligand (1st messenger) attaches to receptor and activates G-proteins
2. G-proteins are the middlemen between the receptor and adenylate cyclase enzyme
3. adenylate cyclase converts ATP to cAMP
4. cAMP (2nd messenger) converts inactive kinase to active kinase, catalyzing the reaction

Question 11

steps taken when the receptor is intracellular

Answer 11

1. lipid soluble ligand penetrates membrane and joins with the receptor (called ligand-receptor complex)
2. the complex travels to the nucleus and attaches to the DNA
3. DNA produces mRNA, which synthesizes proteins, leading to the cellular response

Question 12

is the extracellular or intracellular method faster?

Answer 12

extracellular method is faster, and elicits a response faster as a result

Question 13

3 Types of Signaling

Answer 13

1. Agonist activates signaling-drug is the agonist and opens ion channels
2. Agonist activates G protein-drug generates a second messenger and activates the signaling (extracellular receptor method)
3. Agonist binds to intracellular receptor-transports to the nucleus and uses protein synthesis

Question 14

which type of signaling do the majority of drugs use?

Answer 14

extracellular receptor method

Question 15

agonist

Answer 15

initiates same action of neurotransmitter at receptor

Question 16

full agonist and partial agonist

Answer 16

full-max response

partial-not complete response

Question 17

antagonist

Answer 17

has affinity for receptor but produces no activity

Question 18

competitive antagonist

Answer 18

competes with agonist for receptor site and blocks it

Question 19

noncompetitive antagonist

Answer 19

binds to another part of the receptor to change the shape of the site so the neurotransmitter can’t bind to it

Question 20

receptor-agonist complex

Answer 20

produces activity (a neurotransmitter bound to a receptor)

Question 21

receptor-antagonist complex

Answer 21

produces no activity (blocks site or changes shape of site)

Question 22

phospholipase C inhibitor (PLC)

Answer 22

noncompetitive antagonist that doesn’t affect the actual receptor, it just changes the reaction so that the reaction stops

Question 23

intensity of drug effect characterized by 3 things:

Answer 23

1. affinity
2. intrinsic activity
3. efficacy

Question 24

functional antagonist

Answer 24

when 2 drugs oppose each other–you can get the desired result by manipulating how much of the drug you give that increases cAMP activity
-ex) one drug increases cAMP activity, and the other decreases cAMP activity

Question 25

what happens when cAMP activity is increased?

Answer 25

it converts the inactive kinase enzymes faster resulting in a quicker and better response

Question 26

chemical antagonist

Answer 26

chemically changes structure of agonist

• used as an antidote
• ex) protamine (weak base) will neutralize an overdoes of heparin (weak acid)

Question 27

enzyme inhibition

Answer 27

certain drugs can inhibit certain enzymes

-ex) anti-cholinesterase drugs inhibit cholinesterase, resulting in increased acetylcholine levels

Question 28

cholinesterase

Answer 28

enzyme that breaks down acetylcholine into inactive form

-it relaxes muscles

Question 29

what kind of person would you give anti-cholinesterase drugs to?

Answer 29

someone with an acetylcholine deficiency that may have muscle paralysis

Question 30

phosphodiastrase (PDE)

Answer 30

converts cAMP to ATP (active to inactive)

• if it is inhibited it results in increased cAMP levels
• caffeine is something that can inhibit PDE

Question 31

irreversible enzyme inhibition

Answer 31

some drugs will permanently inhibit enzymes

-ex)COX enzyme allows inflammation production. aspirin inhibits COX enzyme, preventing inflammation

Question 32

enzyme inhibition receptor steps (red and green diagram on PP)

Answer 32

1. empty receptor-ion channel is closed
2. GABA binds to the receptor-ion channel opens
3. chloride ions enter and make cell more negative
4. benzodiazepine enhances the reaction-more chloride ions enter and make you more sleepy

Question 33

which of the drugs is more potent and why?

Answer 33

drug x is more potent because it produces the same response as drug y but with lower dose

Question 34

what happens from point A to B on drug x?

Answer 34

receptors are beginning to be filled, the response is not full yet

Question 35

what happens from point B to C on drug x?

Answer 35

the drug is really beginning to fill the receptors and take effect

Question 36

what happens from point C to D on drug x?

Answer 36

the receptors begin filling up and becoming oversaturated, response begins to plateau

Question 37

nonselective drug

Answer 37

drug isn’t “picky,” it will act on a variety of receptors

Question 38

potency

Answer 38

amount of drug required to produce the desired response

Question 39

therapeutic index

Answer 39

relationship between the effective dose and lethal dose

• narrow margin: unsafe, effective and lethal doses are more similar
• wide margin: safe, effective and lethal doses are far apart