pharmacology summary

Question 1

Affinity –

Answer 1

strength of association between ligand and receptor

Question 2

Efficacy –

Answer 2

ability of an agonist to evoke a cellular response

Question 3

agonist

Answer 3

possess affinity + efficacy

Question 4

antagonist

Answer 4

possess only affinity not efficacy

Question 5

what is pKa

Answer 5

pH at which 50% of drug is ionised

Question 6

Henderson-Hasselbalch equation:

Answer 6

pH – pKa = log(A-/AH) = acid

Question 7

enteral administration route

Answer 7

Oral, sublingual, Rectal

Question 8

parenteral administration route :

Answer 8

IV, IVM, subcutaneous, inhalational

Question 9

Vd < 10L =

Answer 9

vascular compartment

Question 10

Vd 10-30L =

Answer 10

Extracellular water

Question 11

Vd > 30L =

Answer 11

Total body water

Question 12

Vd –

Answer 12

volume in which drug is dissolved

Question 13

higher TR

Answer 13

safer the drug

Question 14

kinetics

Answer 14

elimination at a constant rate

Question 15

Clearance =

Answer 15

volume of plasma cleared of drug in unit time

Question 16

when is a steady state reached

Answer 16

after 5 half lives

Question 17

drug metabolism phase 1

Answer 17

RHS liver – oxidation/reduction/hydrolysis – making drug more polar

Question 18

phase 2 drug metabolism

Answer 18

LHS liver – conjugation

Question 19

Basic processes of renal excretion of drugs:

Answer 19

1. Glomerular filtration
2. Active tubular secretion: anion transporter– acidic cation transporter - basic
3. Passive reabsorption across tubular epithelium

Question 20

Na+flows in –

Answer 20

activation of Na+channels reinforcing – positive feedback

Question 21

K+flows out –

Answer 21

activation of K+channels self-limiting – negative feedback

Question 22

Sympathetic –

Answer 22

fight or flight [T1-L2]

Question 23

Parasympathetic –

Answer 23

rest and digest

Question 24

Neurochemical transmission steps:

Answer 24

1. Precursor taken up
2. Transmitter synthesised and stored
3. Action potential depolarises
4. Calcium influx through voltage-activated calcium channels
5. Calcium induced release of transmitter
6. Receptor activation
7. Enzyme-mediated inactivation of transmitter (cholinergic) or reuptake of transmitter (adrenergic)

Question 25

M1 - Gq

Answer 25

Stimulates phospholipase C
Increases stomach acid secretion

Question 26

M2 - Gi

Answer 26

Inhibition of adenyl cyclase,
opening K+ channels
- Decreased HR

Question 27

M3 - Gq

Answer 27

Stimulates phospholipase C
Increased saliva secretion and
bronchoconstriction

Question 28

β1 - Gs

Answer 28

Stimulation of adenylyl cyclase
Increased HR and force

Question 29

β2 - Gs

Answer 29

Stimulation of adenylyl cyclase
Relaxation of bronchial and vascular smooth muscle

Question 30

α1 - Gq

Answer 30

Stimulation of phospholipase C
Contraction of vascular smooth muscle

Question 31

α2 - Gi

Answer 31

Inhibition of adenylyl cyclase
Inhibition of NA release