info from slides

Question 1

vasotec

Answer 1

enalapril maleate. ace inhibitor used to treat high BP

Question 2

trandate

Answer 2

labetalol hydrochloride. beta 1 and 2 blocker. also blocks alpha 1. reduces heart strain and bp

Question 3

albuterol sulfate

Answer 3

proventil HFA

Question 4

additive interactions

Answer 4

1+1=2 sum of two effects is equal to each of them given separately but at the same time

Question 5

Synergistic Interactions:

Answer 5

The summation of each individual drug’s activity exceeds the sum of the two individual drugs”

Question 6

Potentiation:

Answer 6

One drug (which has no direct effect) increases the response of the other drug, which normally has a lesser effect”

Question 7

law of mass action drug receptor inter actions

Answer 7

reversible because drug receptor complex is reversible. effects are proportional to # of receptors occupied. effects plateau because of limitation of total # of receptors. drug effects are proportional to dose

Question 8

intrinsic activity

Answer 8

measure of drugs effectiveness of causing a response (efficacy) An antagonistic drug’s intrinsic activity is 0, meaning it would bind but have no response. An intrinsic activity of 1 would be a full agonist, and 0.5 would equal a partial agonist.

Question 9

tolerance

Answer 9

increased amount of drug needed to produce same effect

Question 10

desensitization

Answer 10

longterm exposure makes tissues/cells less responsive over time

Question 11

down regulation

Answer 11

ccurs over a longer period than desensitization (hours to days to weeks)

• Receptors are internalized and eliminated
• Consequently, the effects of down- regulation are longer-lasting

Question 12

potency

Answer 12

The amount of drug necessary to produce an effect of a given magnitude”

• Potencies are compared by the amount of drug required to produce 50% of the maximal effect (EC50)
• Differences in potency can be overcome by simply giving more drug.

Question 13

efficacy

Answer 13

he ability of a drug to elicit a response when it interacts with a receptor”

• Think of fentanyl being more potent than morphine and both are more effica- cious for pain than aspirin.
• Efficacy is generally more important than potency.

Question 14

therapeutic index

Answer 14

herapeutic Index =
The TD50/ED50
-The ratio of the drug doses that
produces a specified toxic effect in
50% of the population vs. the dose
that produces a specified therapeutic
effect in 50% of the population.
2 or lower is not safe

Question 15

signal amplification

Answer 15

One drug molecule interacts with many receptors.

2) The activated receptors can persist for longer than the original drug ligand/receptor complex existed.

Question 16

three aspects of drug receptor function

Answer 16

Receptors determine the nature and characteristics of the “Drug Concentration-Effect Curve”.

2) Receptors function as regulatory proteins and part of chemical signaling mechanisms that provide targets for drugs.
3) Receptors determine the therapeutic and toxic effects of drugs on a critter.

Question 17

types of receptors

Answer 17

regulatory proteins such as
neurotransmittors or hormones
2) Enzymes
3) Transport proteins such as Na+/K+ ATPase
4) Structural proteins such as tubulin, the receptor for colchicine

Question 18

spare receptor concept

Answer 18

1) Maximal response can be achieved by an agonist even if only a fraction of the receptors are occupied.
2) Sensitivity of the cell to an agonist concentration depends on affinity of receptors for the drug and total receptor concentration.

Question 19

bioavailability

Answer 19

The fraction of an

administered drug that reaches the systemic circulation”

Question 20

Factors affecting Bioavailability

Answer 20

Solubility characteristics of the drug. Chemical Stability in the GI tract. Drug formulation

Question 21

Volume of Distribution

• This distribution is mostly dependent on three things:

Answer 21

Blood flow, fat/water solubility, and protein binding.

Question 22

This half-life assumption assumes “First Order Kinetics”

Answer 22

First Order Kinetics: “The rate of drug metabolism and elimination is directly proportional to the concentration of free drug”

Question 23

clearance rate=

Answer 23

(.693 x Vd)/T(1/2/)

Question 24

Zero-Order Kinetics

Answer 24

ome drugs are administered in such high quantities (dosages) that they are eliminated by a constant AMOUNT (not proportion) over time because they’ve overwhelmed clearance mechanisms

Question 25

earance, half-life, and volume of distribution are all related to

Answer 25

drug dosing. Sooooo….it means that repeated dosing of a drug won’t allow for the drug to “accumulate” in the critter unless the dosing interval is < 4 half- lives.
• ….and accumulation of a drug is necessary in order for the drug to reach a “steady-state” in the critter’s plasma.

Question 26

Target Concentration”

Answer 26

The drug concentration that will produce the desired therapeutic effect.”

Question 27

Loading Dose=

Answer 27

(Vd)x(Target plasma concentration)/ Bioavailability %

Question 28

Maintenance Dosing=

Answer 28

(Cl)x(Target plasma concentration)/bioavailability%. Dosing rate X Dosing interval

Question 29

What does Biotransformation accomplish?

Answer 29

Biotransformation can shorten a drug’s biological half-life: if an anesthetic is very non-polar (and thus enters the brain easily) biotransforming it into a polar molecule can greatly decrease its activity (and biological half-life.) Alternatively, biotransformation can turn non- biologically active chemicals into active drugs or convert drugs into even more active forms.

Question 30

two types of biotransformation

Answer 30

Phase I Biotransformation:Metabolizes the drug into a more polar form. Phase II Biotransformation:Conjugates the drug with another chemical (such as acetylation)

Question 31

induced vs inhibited cytochrome p450

Answer 31

Induced P450 enzymes metabolize drugs faster.

Inihibited P450 enzymes metabolize drugs slower.

Question 32

Semiautonomouspart of ANS in the GI tract

Answer 32

Twocomponents: 1) Myenteric plexus
(plexus of Auerbach)
2) Submucous plexus (plexus of Meissner)
These neurons send sensory input to the parasympathetic and sympathetic nervous systems and receives motor output from them

Question 33

FEEDBACK OF NOREPINEPHRINE

Answer 33

BARORECEPTORS SENSE INCREASED PRESSURE. They begin to fire and cause vagal stimulation which slows HR. So net effect is increase in SVR through alpha receptors and decrease in HR even though it has direct chronotropic effects

Question 34

autoreceptor

Answer 34

If the presynaptic neuron is inhibited by the chemical it produces (such as norepinephine) i

Question 35

heteroreceptor

Answer 35

f the presynaptic neuron is inhibited by chemicals that are released by neurons with which it has a synapse (and which that presynaptic neuron doesn’t produce)

Question 36

Six Steps of Cholinergic Neurotransmission

Answer 36

1. )synthesis of ACH (INHIBITED BY HEMICHOLINIUM) rate limiting and has to be actively transported
2. ) uptake into storage vesicles where it is protected from degradation
3. )release of ACH
4. )binds to postsynaptic receptor
5. )deagradtion of ACH by ACHe in synaptic cleft
6. )recycling of choline by Na transport which allows it to get into membrane