pharmacology

Question 1

pharmacodynamics

Answer 1

what the drug does to the body

Question 2

pharmacokinets

Answer 2

what the body does to the drug

Question 3

for a drug to be useful, it has to work with a degree of ______

Answer 3

selectivity

Question 4

examples of regulatory proteins

Answer 4

enzymes
carrier molecules
ion channels receptors

Question 5

what is affinity determined by

Answer 5

the chemical bonds between a ligand and its receptor

Question 6

type of chemical bonds between ligand and receptor

Answer 6

ionic
hydrogen
aromatic interaction

Question 7

what is efficacy?

Answer 7

efficacy is the ability for an agonist to complete a cellular response

Question 8

how do antagonists work?

Answer 8

bind to receptors (usually reversibly) but do not activate them
possesses affinity but lack efficacy
block receptor activation by agonists

Question 9

EC50

Answer 9

the concentration of agonist that elicits a half maximal response

Question 10

are the binding pf agonists and antagonists reversible or non-reversible?

Answer 10

reversible

Question 11

why is the binding of agonists and antagonists competitive?

Answer 11

they bind to the same site

Question 12

how can reversible competitive antagonism be overcome

Answer 12

increase the concentration of agonists

Question 13

non - competitive antagonism

Answer 13

agonist binds to the site and antagonist binds to a seperaate site

Question 14

in non competitive antagonism, can both the agonist and antagonist bind to the receptor simultaneously and reversibly

Answer 14

yes.

Question 15

what are receptors made of

Answer 15

macromolecules

Question 16

what are receptors?

Answer 16

the sensing elements of chemical communication within the body

Question 17

most cells are exposed to a common extracellular fluid. why do they respond differently?

Answer 17

because of the particular receptor types they express

Question 18

major types of receptors

Answer 18

ligand gated ion channels
G protein - coupled receptors
kinase linked receptors
nuclear receptors

Question 19

ion channels…

Answer 19

when open conduct selected ions passively down their electrochemical gradients

Question 20

example of ligand gated ion channels

Answer 20

nicotinic acetylchlorine receptor of skeletal muscle and neurones

Question 21

basic structure of G protein coupled receptors

Answer 21

integral membrane protein
single polypeptide with extracellular NH2and intracellular COOH terminal
contains 7 transmembrane proteins
may sometimes function as dimers

Question 22

basic structure of G proteins

Answer 22

peripheral membrane protein
consists of 3 polypeptide subunits
contains a guanine binding site

Question 23

how are G protiens activated

Answer 23

binding of agonists to the GPCR

Question 24

what is the guanine nucleoside site occupied with when inactive on a Gprotein

Answer 24

GDP

Question 25

The activation of GPCR activates what

Answer 25

a conformational change

Question 26

where is the conformational change transmitted to

Answer 26

the G protein alpha subunit

Question 27

the activation of a GPCR releases the GDP and allows what

Answer 27

the GTP to bind in its place

Question 28

drug disposition

Answer 28

absorption
distribution
metabolism
excretion

Question 29

the linked processes of metabolism and excretion is known as what?

Answer 29

elimination

Question 30

factors controlling drug absorption

Answer 30

solubility, chemical stability, lipid to water partition coefficient

Question 31

absorption of drugs occurs how?

Answer 31

by simple diffusion across membranes

Question 32

acids donate or accept protons

Answer 32

donate

Question 33

bases donate or accept protons

Answer 33

accept

Question 34

degree of ionisation depends on what

Answer 34

pKa of the drug and pH

Question 35

pKa =

Answer 35

pH at which 50% of the drug is ionised

Question 36

absorption of weak acids is facilitated by

Answer 36

pH of the stomach lumen

Question 37

when are bases readily absorbed

Answer 37

when they reach the small intestine

Question 38

the majority of absorption take place in the

Answer 38

small intestine

Question 39

why does absorption take place in the small intestine?

Answer 39

large surface area compared compared to the stomach

Question 40

are weak acids and weak bases absorbed readily

Answer 40

yes

Question 41

are strong acids and bases absorbed readily?

Answer 41

no

Question 42

acidic drugs become less ionised in what environment

Answer 42

an acid environment

Question 43

basic drugs become less ionised in what environment

Answer 43

a basic environment

Question 44

factors affecting gastrointestinal absorption

Answer 44

gastrointestinal motility
pH at the absorption site
blood flow
the way in which the tablet is manufactured

Question 45

4 main compartments

Answer 45

plasma water
interstitial water
intracellular water
transcellular water

Question 46

which drugs can move freely by diffusiom

Answer 46

drugs that are not bound to plasma protein

Question 47

can ionised or unionised drugs move readily by diffusion

Answer 47

only unionised

Question 48

volume of distribution is less than 10L

Answer 48

implies that the drug is largely contained in the vascular compartment

Question 49

volume of distribution between 10 and 30 L

Answer 49

suggests that the drug is largely restricted to extracellular water

Question 50

volume of distribution greater than 30L

Answer 50

may indicate distribution throughout total body water or accumulation in certain tissues