Receptors

Question 0

Propranolol [inderal]

Answer 0

Cell surface receptor antagonist

beta adrenoceptor blockers for angina, MI, heart failure, High BP, performance anxiety

Question 1

Drug mechanisms

Answer 1

antagonists of cell surface receptors 
antagoinsts of nuclear receptors 
enzyme inhibitors 
ion channel blockers 
transport inhibitors 
inhibitors of signal transduction proteins

Question 2

Tamoxifen [Nolvadex]

Answer 2

Nuclear receptor antagonist

Estrogen receptor antagonists for prevention and treatment of breast cancer

Question 3

Aspirin, ibuprofen [Motrin]

Answer 3

Inhibits enzymes

cyclooxygenase inhibitors for pain relief, particularly due to arthritis

Question 4

Diltiazem [Cardizem]

Answer 4

Block ion channels

calcium channel blocker for angina and High BP

Question 5

Fluoxetine [Prozac]

Answer 5

Transport inhibitor
selective serotonin reuptake inhibitor
for treatment of depression

Question 6

Sildenafil [Viagra]

Answer 6

inhibits signal transduction proteins
Type 5 phosphodiesterase inhibitor for erectile dysfunction
cGMP impt in vasodilation in veins
if inhibit it, builds up and causes more vasodilation

Question 7

Phenylephrine [Neosynephrine]

Answer 7

activates cell surface receptor
alpha adrenoceptor agonists for nasal congestion
vasoconstriction of blood vessels in nose prevents exudation into tissues

Question 8

Conjugated equine estrogen [Premarin]

Answer 8

activate nuclear receptor

estrogen receptor agonists for hormone replacement therapy in postmenopausal women

Question 9

Pralidoxime [Protopam]

Answer 9

activates enzymes

reactivator of cholinesterase after poisoning with nerve gas or organophosphate pesticide

Question 10

Minoxidil [Rogaine]

Answer 10

open ion channels

Potassium channel openers for hair regrowth

Question 11

Drug that is an enzyme

Answer 11

Alteplase [Activase]

thrombolytic therapy for acute MI

Question 12

Vincristine or Vinblastine

Answer 12

disrupt structural proteins

vinca alkaloids for cancer

Question 13

Cyclophosphamide [Cytoxan]

Answer 13

covalently link to macromolecules

DNA alkylating agents for the treatment of cancer

Question 14

Dimercaprol [penicillamine]

Answer 14

binds free molecules or atoms

chelating agent for heavy metal poisoning

Question 15

Mannitol

Answer 15

exerts action due to physical property

osmotic diuretic for edema

Question 16

affinity constant

Answer 16

Kaff = k1/k2

higher the better attraction

Question 17

potency

Answer 17

amount of drug required to elicit a response
characteristic that can be compared by use of EC50 values
often expressed as dose of a drug required to achieve 50% of the desired therapeutic effect ED50 (effective dose)

Question 18

the smaller the Ec50

Answer 18

the more potent the drug

Question 19

Quantal

Answer 19

all or none response, population

Question 20

Graded

Answer 20

range of responses, individual

Question 21

analogs of active drugs are sought to

Answer 21

be more potent 
more completely absorbed 
less rapidly metabolized 
less bound to plasma proteins 
less toxic

Question 22

Efficacy

Answer 22

ability of agonist to cause the receptor to assume an active conformation
represented by k3
maximal response a drug can produce

Question 23

Parital agonist

Answer 23

dual activity
produces biologic response but cannot produce 100% of the biologic response even at very high dose
partially inhibit the response to full agonists at the same receptor type

Question 24

spare receptor

Answer 24

presence shifts the agonist concentration effect curve to the left of the Kd for binding of agonist to receptor makes tissue more sensitive to an agonist without changing its affinity for the receptor

Question 25

Kd

Answer 25

when 50% of drug is bound to receptor and 50% of drug is not bound to the receptor

Question 26

Therapeutic Index

Answer 26

LD50/ED50 | measure of drug safety

Question 27

Margin of safety

Answer 27

LD1/ED99 | more realistic measure of drug safety

Question 28

Protective index

Answer 28

is ED50 | undesirable effect/ ED50 (desireable effect)

Question 29

Noncompetitve antagonist

Answer 29

reduces the maximal response that an agonist can produce

Question 30

chemical antagonist

Answer 30

interacts directly with the drug being antagonized to remove it or prevent it from binding to target

Question 31

Drug tolerance

Answer 31

diminished response to drug over time

Question 32

Desensitization

Answer 32

rapid process involving continuous exposure to drug, altering the receptor so that it cannot produce a response

Question 33

Tachyphylaxis

Answer 33

rapid development of tolerance several doses over a short time deplete the pool reducing the response to successive doses

Question 34

Potentiation

Answer 34

5+0 = 20

Question 35

Synergism

Answer 35

4+6 = 16

Question 36

Selectivity

Answer 36

confered by either the cell type specificity of receptor subtypes the cell type specificity of receptor effector coupling

Question 37

dose effect relationship

Answer 37

predicts the effects of changing dose reveal the necessary trade offs between efficacy and adverse effects facilitate comparisons of alternative meds for the same indication ehnace understanding of how best to use receptor blockers