Pharmacodynamics- theory and checmicals

Question 1

What is the action of competitive antagonists?

Answer 1

Competitive antagonists reversibly block receptors without activation and their effects are surmountable by increasing the dose of an agonist.

Question 2

What is physiological antagonism?

Answer 2

Physiological antagonism occurs when two drugs produce opposing physiological effects via different biochemical pathways.

Question 3

Selective Serotonin Reuptake Inhibitors (SSRIs) like fluoxetine are used to treat depression, and loop diuretics like furosemide are used for the treatment of oedema. These are examples of drugs inhibiting ???

Answer 3

are examples of drugs inhibiting transporters

Question 4

For what conditions are Alpha 1-adrenoceptor agonists prescribed? Eg phenylephrine

Answer 4

Alpha 1-adrenoceptor agonists are used as nasal decongestants due to their vasoconstrictor effect.

Question 4

Drugs like nitroglycerine and isosorbide dinitrate activate guanylate cyclase to relax vascular smooth muscle for angina relief. these are examples of drugs that ACTIVATE ???

Answer 4

examples of drugs that activate enzymes

Question 4

Angiotensin II receptor blockers like losartan and β-adrenoceptor antagonists like propranolol are used to treat conditions such as high blood pressure and heart failure. These are examples of drugs inhibiting ???

Answer 4

examples of drugs inhibiting cell surface receptors

Question 5

What are irreversible antagonists?

Answer 5

Irreversible antagonists have reactive chemical groups that form covalent linkages with receptors and their effects are not surmountable by increasing the dose of an agonist.

Question 6

Kinase linked receptors, such as tyrosine kinase receptors, are activated following dimerization and their kinase domain is activated via ???

Answer 6

phosphorylation.

Question 7

What is the use of enzyme activators? HINT: think of disease process driven by lack of …

Answer 7

Enzyme activators are used when the disease process is driven by too limited or lack of enzyme activity.

Question 8

What determines a drug’s pharmacological activity? the combination of a drug’s ??? and distribution of its target receptor in cells and tissues

Answer 8

A combination of a drug’s specificity and the distribution of its target receptor in cells and tissues

Question 9

What is the therapeutic use of GABAA chloride channel openers?

Answer 9

GABAA chloride channel openers like benzodiazepines are used for treating anxiety.

Question 10

Cyclooxygenase inhibitors like aspirin and ACE inhibitors like captopril are used for pain relief and to treat high blood pressure, respectively. These are enzyme INHIBITORS or ACTIVATORS?

Answer 10

INHIBITORS

Question 11

a medicine is a drug in a formulation that allows appropriate delivery. May involve improving:
* ???
* Stability
* Taste
* Physical form

Answer 11

Absorption

Question 11

TRUE or FALSE: A drug is any substance or product that is used or intended to be used to modify or
explore physiological systems or pathological states for the benefit of the recipient

Answer 11

TRUE

Question 11

drugs interact with biomolecules to exert chemical influence on ???

Answer 11

cellular function

Question 11

Most drug targets are proteins such as
- Receptors, enzymes, carrier molecules (i.e. transporters) and ??? channels.

Answer 11

ion channels

Question 12

TRUE or FALSE: drugs include endogenous substances such as hormones, neurotransmitters, ions, antibodies

Answer 12

TRUE

Question 13

The interaction between drug molecules and drug targets impacts
??? function

Answer 13

physiological function

Question 14

Agonists occupy receptors and activate or deactivate (?) cell processes

Answer 14

activate

Question 15

A combination of a drug’s specificity
and the distribution of its target receptor in cells and tissues determines its ???

Answer 15

pharmacological activity

Question 16

Antagonists occupy receptors but do not elicit a tissue response, hence also referred to as “inhibitors” as they inhibit a ??? response

Answer 16

physiological
response

Question 17

Drug specificity refers to the relative
selectivity that a drug exhibits for a ???

Answer 17

receptor

Question 18

Small changes in a drug’s chemical structure can cause loss OR gain (?) of activity because it no longer binds to its receptor. Alternatively, structure can also be manipulated to increase activity (whether agonistic or antagonistic)

Answer 18

loss only

Question 19

TRUE or FALSE: No drug is completely specific for its target receptor

Answer 19

TRUE

Question 20

Drug potency refers to the ??? of drug required to produce an effect

Answer 20

concentration

Question 20

One drug is more potent than another if it acts on the same target (receptor) but elicits the same effect (i.e. EC50) at a lower OR higher (?) concentration

Answer 20

lower concentration

Question 20

Drug affinity is a thermodynamic property reflecting the strength with which a drug binds to its target. Often measured as the equilibrium dissociation constant, ???

Answer 20

Kd

Question 21

Drug efficacy is the tendency of the drug to activate a tissue response once bound to its ???. Measured by differences in maximal response

Answer 21

receptor

Question 22

Competitive antagonists REVERSIBLY or IRREVERSIBLY (?) block receptors without activation. Effects surmountable by increasing agonist dose e.g. pseudoephedrine (adrenergic receptor agonist) vs propranolol (competitive adrenergic antagonist). Must have same receptor binding site

Answer 22

REVERSIBLY

Question 23

what type of antagonist has reactive chemical groups that form covalent linkages with receptors? HINT: Rarely used clinically, more useful in in vitro research

Answer 23

irreversible antagonists

Question 24

what type of antagonist doesn't bind the same binding site on a receptor as the agonist?

Answer 24

non-competitive antagonists

Question 25

what type of antagonist binds an allosteric site causing a conformational change in the receptor that reduces the binding and response to an agonist AND effects are NOT surmountable?

Answer 25

non-competitive antagonists

Question 26

??? antagonism describes the binding of one drug to another, covalently or otherwise

Answer 26

chemical

Question 27

Antagonist effects the rate of absorption, excretion or metabolic degradation of another drug. what type of antagonism is this?

Answer 27

Pharmacokinetic Antagonism

Question 28

Histamine induces gastric acid secretion from parietal cells (stomach) whereas omeprazole blocks acid secretion by a totally different pathway - Omeprazole is a physiological antagonist of histamine. This is an example of what type of antaognism?

Answer 28

physiological antagonism

Question 28

Warfarin (anticoagulant) hepatic metabolism (inactivation) is accelerated by phenobarbital (induces liver enzymes), which reduces its anticoagulant effects. this is an example of what type of antagonism?

Answer 28

pharmacokinetic antagonism

Question 29

example of ion channels: IP3 receptors nicotinic acetylcholine receptors P???

Answer 29

P2X receptors

Question 29

example of G-protein coupled receptors: - P??? receptors

Answer 29

P2Y receptors

Question 30

7 transmembrane domaine G-protein coupled receptor and G protein interact at the interface of the membrane and ???

Answer 30

cytoplasm

Question 31

G-coupled protein receptors can be triggered by neurotransmitters which also activates ???

Answer 31

ligand-gated ion channels

Question 32

Kinase linked receptors (catalytic receptors): tyrosine kinase receptors are activated following ???

Answer 32

dimerisation

Question 33

Kinase linked receptors: Kinase domain is activated via ???. Downstream signalling molecules signal via ??? reactions

Answer 33

phosphorylation

Question 34

examples of Kinase linked receptors (catalytic receptors): - cytokine receptors - integrins - tyrosine ???

Answer 34

tyrosine kinase

Question 35

what type of receptors are typically activated by steroidal or non-steroidal hormones. Agonists diffuse across membrane (or via transporter). Bind to receptor in cytoplasm or nucleus and alter transcription in the nucleus (long-term changes)

Answer 35

nuclear receptors

Question 36

Drugs activating cell surface receptors: Alpha 1-adrenoceptor agonists constrict arterioles (vasoconstrictor) e.g. phenylephrine, oxymetazoline For use as nasal decongestants agonist or antagonist?

Answer 36

agonist

Question 37

GABAA chloride channel openers for treating anxiety includes: benzodiazepines - Valium This is an agonist or antagonist for ion channel opening?

Answer 37

agonist

Question 37

Potassium channel openers for vasodilation include: Minoxidil This is an agonist or antagonist for ion channel opening?

Answer 37

agonist

Question 38

mu (μ)-opioid receptor agonists for analgesia e.g. morphine. Endogenous ligand of μ-opioid receptor is endomorphin. agonist or antagonist?

Answer 38

agonist

Question 39

Drugs activating nuclear receptors: Oestrogen receptor agonists for hormone replacement therapy in post-menopausal women e.g. ???

Answer 39

estradiol

Question 40

what is an example of the drug molecule being the same structure as the native ligand? Hint: drug that activates nuclear receptors

Answer 40

estradiol

Question 41

Glucocorticoid receptor agonists for treatment of inflammation * Hydrocortisone = endogenous * Dexamethasone = non-endogenous these agonists activate ??? receptors

Answer 41

activating nuclear receptors

Question 42

Activators of guanylate cyclase to relax vascular smooth muscle for angina relief e.g. nitric oxide (NO)-generating organic nitrates * Nitroglycerin * Isosorbide dinitrate agonists drugs that activate ???

Answer 42

enzymes

Question 43

Reactivators of cholinesterase after poisoning with nerve agent or organophosphate pesticides. e.g. ??? is an antidote which can cross the BBB. An agonist that activates enzymes

Answer 43

Pralidoxime

Question 44

Calcium channel blockers for angina and high blood pressure e.g. ??? Antagonist

Answer 44

Amlodipine

Question 45

Sodium channel blockers to prevent propagation of nerve signals. e.g. ??? used as local anaesthetic antagonist

Answer 45

Lidocaine

Question 46

Angiotensin II receptor (type1) blockers (AT1 antagonists) for treating high BP, heart failure, chronic renal insufficiency. e.g. ??? and ??? the sartans (inhibit cell surface receptors)

Answer 46

losartan, valsartan

Question 47

β-Adrenoceptor antagonists for treating angina, myocardial infarction, high BP include: ???, metoprolol, atenolol (inhibit cell surface receptors)

Answer 47

propanolol

Question 48

Mineralocorticoid receptor antagonists for oedema due to liver cirrhosis and heart failure. Is an aldosterone antagonist. (Drugs inhibiting nuclear receptors)

Answer 48

spironolactone

Question 49

Oestrogen receptor antagonists for the treatment of breast cancer. ??? can be used but efficacy is limited due to the risk of drug resistance (Drugs inhibiting nuclear receptors)

Answer 49

tamoxifen

Question 50

Cyclooxygenase inhibitors inhibit prostaglandin (inflammatory mediator) synthesis to provide pain relief. Known as non-steroidal anti-inflammatory drugs (NSAIDS). e.g. ibuprofen, ??? (Drugs inhibiting enzymes)

Answer 50

aspirin

Question 51

Angiotensin Converting Enzyme (ACE) Inhibitors for high blood pressure, heart failure, and chronic renal insufficiency. e.g. captopril, ??? (Drugs inhibiting enzymes)

Answer 51

ramipril

Question 52

Transporters bind to and shuttle membrane impermeable ligands across the cell membrane e.g. ??? transporter, Serotonin transporter (SERT)

Answer 52

Noradrenaline

Question 53

TRUE or FALSE: Some drugs bind to transporters and cause changes that prevent proper functioning of transporters e.g. cocaine binding to noradrenaline transporter. Changes in the concentration of specific solutes (e.g. noradrenaline in synapses) mediate the effects of inhibitors of transporters.

Answer 53

TRUE

Question 54

Selective Serotonin Reuptake Inhibitors (SSRIs) for the treatment of depression and anxiety are agonists inhibiting ??? e.g. Fluoxetine, paroxetine, citalopram

Answer 54

transporters

Question 55

Inhibitors of Na-2Cl-K symporter (loop diuretics) in renal epithelial cells to increase urine and sodium output for the treatment of oedema e.g. ???, bumetanide (Drugs inhibiting transporters)

Answer 55

Furosemide

Question 56

Drug potency refers to the ??? of drug required to produce an effect. One drug is more potent than another if it acts on the same target (receptor) but elicits the same effect (i.e. EC50) at a lower ???

Answer 56

concentration concentration